Marijuana Grower's Handbook - Part 1 of 33
"Marijuana : The Plant"
Cannabis probably evolved in the Himalayan foothills, but its
origins are clouded by the plant's early symbiotic relationship
with humans. It has been grown for three products - the seeds,
which are used as a grainlike food and animal feed and for oil;
its fiber, which is used for cloth and rope; and its resin, which
is used medically and recreationally since it contains the group
of psychoactive substances collectively known as Tetra-hydrocannibinol,
usually referred to as THC. Plants grown for seed or fiber are
usually referred to as hemp and contain small amounts of THC.
Plants grown for THC and for the resin are referred to as
marijuana. Use of cannabis and its products spread quickly
throughout the world. Marijuana is now cultivated in climates
ranging from the Arctic to the equator. Cannabis has been
evolving for hundreds of thousands of generations on its own and
through informal breeding programs by farmers. A diverse group of
varieties has evolved or been developed as a result of breeders'
attempts to create a plant that is efficient at producing the
desired product, which flourishes under particular environmental
conditions. Cannabis easily escapes from cultivation and goes
"wild." For instance, in the American midwest, stands
of hemp "weed" remain from the 1940's plantings. These
plants adapt on a population level to the particular
environmental conditions that the plants face; the stand's
genetic pool, and thus the plants' characteristics, evolve over a
number of generations. Varieties differ in growth characteristics
such as height, width, branching traits, leaf size, leaf shape,
flowering time, yield, potency, taste, type of hig, and aroma.
For the most part, potency is a factor of genetics. Some plants
have the genetic potential of producing high grade marijuana and
others do not. The goal of the cultivator is to allow the high
THC plants to reach their full potential. Marijuana is a fast
growing annual plant, although some varieties in some warm areas
overwinter. It does best in a well-drained medium, high in
fertility. It requires long periods of unobstructed bright light
daily. Marijuana is usually dioecious; plants are either male or
female, although some varieties are monoecious - they have male
and female flowers on the same plant.
Marijuana's annual cycle begins with germination in the early
spring. The plant grows vigorously for several months. The plant
begins to flower in the late summer or early fall and sets seed
by late fall. The seeds drop as the plant dies as a result of
changes in the weather. Indoors, the grower has complete control
of the environment. The cultivator determines when the plants are
to be started, when they will flower, whether they are to produce
seed and even if they are to bear a second harvest.
Marijuana Grower's Handbook - Part 2 of 33
by pH Imbalance
"Choosing A Variety"
Gardeners can grow a garden with only one or two varieties or
a potpourri. Each has its advantages. Commercial growers usually
prefer homogenous gardens because the plants tatse the same and
mature at the same time. These growers usually choose fast
maturing plants so that there is a quick turnaround. Commercial
growers often use clones or cuttings from one plant so that the
garden is genetically idential; the clones have exactly the same
growth habits and potency.
Homegrowers are usually more concerned with quality than with
fast maturity. Most often, they grow mixed groups of plants so
they have a selection of potency, quality of the high, and taste.
Heterogeneous gardens take longer to mature and have a lower
yield than homogenous gardens. They take more care, too, because
the plants grow at different rates, have different shapes and
require varying amounts of space. The plants require individual
care.
Marijuana grown in the United States is usually one of two main
types: inidica or sativa. Indica plants originated in the Hindu-Kush
valleys in central Asia, which is located between the 25-35
latitudes. The weather there is changeable. One year there may be
drought, the next it might be cloudy, wet, rainy or sunny. For
the population to survive, the plant group needs to have
individuals which survive and thrive under different conditions.
Thus, in any season, no matter what the weather, some plants will
do well and some will do poorly.
Indica was probably developed by hash users for resin content,
not for flower smoking. The resin was removed from the plant. An
indication of indica's development is the seeds, which remain
enclosed and stick to the resin. Since they are very hrd to
disconnect from the plant, they require human help. Wild plants
readily drop seeds once they mature. Plants from the same line
from equatorial areas are usually fairly uniform. These include
Colombians and central Africans. Plants from higher latitudes of
the same line sometimes have very different characteristics.
These include Southern Africans, Northern Mexicans, and indicas.
The plants look different from each other and have different
maturities and potency. The ratio of THC (the ingredient which is
psychoactive) to CBD (its precursor, which often leaves the
smoker feeling disoriented, sleepy, drugged or confused) also
varies.
High latitude sativas have the same general characteristics: they
tend to mature early, have compact short branches and wide, short
leaves which are dark green, sometimes tinged purple.
Indica buds are usually tight, heavy, wide and thick rather than
long. They smell "stinky", "skunky", or
"pungent" and their smoke is thick - a small toke can
induce coughing. The best indicas have a relaxing "social
high" which allow one to sense and feel the environment but
do not lead to thinking about or analyzing the experience.
Cannabis sativa plants are found throughout the world. Potent
varieties such as Colombian, Panamanian, Mexican, Nigerian,
Congolese, Indian and Thai are found in equatorial zones. These
plants require a long time to mature and ordinarily grow in areas
where they have a long season. They are usually very potent,
containing large quanities of THC and virtually no CBD. They have
long, medium-thick buds when they are grown in full equatorial
sun, but under artificial light or even under the temperate sun,
the buds tend to run (not fill out completely). The buds usually
smell sweet or tangy and the smoke is smooth, sometimes
deceptively so. The THC to CBD ratio of sativa plants gets lower
as the plants are found further from the equator. Jamaican and
Central Mexican varieties are found at the 15-20th latitudes. At
the 30th latitude, varieties such as Southern African and
Northern Mexican are variable and may contain equal amounts of
THC and CBD, giving the smoker and buzzy, confusing high. These
plants are used mostly for hybridizing. Plants found above the 30th
latitude usually have low levels of THC, with high levels of CBD
and are considered hemp. If indica and sativa varieties are
considered opposite ends of a spectrum, most plants fall in
between the spectrum. Because of marijuana and hemp's long
symbiotic relationship with humans, seeds are constantly procured
or traded so that virtually all populations have been mixed with
foreign plants at one time or another.
Even in traditional marijuana-growing countries, the marijuana is
often the result of several cross lines. Jamaican ganja, for
example, is probably the result of crosses between hemp, which
the English cultivated for rope, and Indian ganja, which arrived
with the Indian immigrants who came to the country. The term for
marijuana in Jamaic in ganja, the same as in India. The
traditional Jamaican term for the best weed is Kali, named for
the Indian killer goddess.
Marijuana Grower's Handbook - Part 3 of 33
"Growth and Flowering"
The cannabis plant regulates its growth and flowering stages
by measuring the changes in the number of hours of uniterrupted
darkness to determine when to flower. The plant produces a
hormone (phytochrome) begining at germination. When this chemical
builds up to a critical level, the plant changes its mode from
vegetative growth to flowering. This chemical is destroyed in the
presence of even a few moments of light. During the late spring
and early summer there are many more hours of light than darkness
and the hormone does not build up to a critical level. However,
as the days grow shorter and there are longer periods of
uniterrupted darkness, the hormone builds up to a critical level.
Flowering occurs at different times with different varieties as a
result of the adaptation of the varieties to the environment.
Varieties from the 30th latitude grow in an area with a temperate
climate and fairly early fall. These plants usually trigger in
July or August and are ready to harvest in September or October.
Southern African varieties often flower with as little as 8 or 9
hours of darkness/15 to 16 hours of light. Other 30th latitude
varieties including most indicas flower when the darkness cycle
lasts a minimum of 9 to 10 hours. Jamaican and some Southeast
Asian varieties will trigger at 11 hours of darkness and ripen
during September or October.
Equatorial varieties trigger at 12 hours or more of darkness.
This means that they will not start flowering before late
September or early October and will not mature until late
November or early December. Of course, indoors the plants' growth
stage can be regulated with the flick of a switch. Nevertheless,
the plants respond to the artificial light cycle in the same way
that they do to the natural seasonal cycles. The potency of the
plant is related to its maturity rather than chronological age.
Genetically identical 3 month and 6 month-old plants which have
mature flowers have the same potency. Starting from seed, a six
month old plant flowers slightly faster and fills out more than a
3 month old plant.
Marijuana Grower's Handbook - Part 4 of 33
"Choosing a Space"
Almost any area can be converted to a growing space. Attics,
basements, spare rooms, alcoves and even shelves can be used.
Metal shacks, garages and greenhouses are ideal areas. All spaces
must be located in an area inaccessible to visitors and invisible
from the street. The ideal area is at least 6 feet high, with a
minimum of 50 square feet, an area about 7 feet by 7 feet. A
single 1,000 watt metal halide or sodium vapor lamp, the most
efficient means of illuminating a garden, covers an area this
size.
Gardeners who have smaller spaces, at least one foot wide and
several feet long, can use fluorescent tubes, 400 watt metal
halides, or sodium vapor lamps.
Gardeners who do not have a space even this large to spare can
use smaller areas (See part 17 - "Novel Gardens").
Usually, large gardens are more efficient than small ones. The
space does not require windows or outside ventilation, but it is
easier to set up a space if it has one or the other. Larger
growing areas need adequate ventilation so that heat, oxygen, and
moisture levels can be controlled. Greenhouses usually have vents
and fans built in. Provisions for ventilation must be made for
lamp-lit enclosed areas. Heat and moisture buildup can be
extraordinary. During the winter in most areas, the heat is
easily dissipated; however, the heat buildup is harder to deal
with in hot weather. Adequate ventilation or air coolers are the
answer.
Marijuana Grower's Handbook - Part 5 of 33
"Preparing the Space"
The space is the future home and environment of the plants. It
should be cleaned of any residue or debris which might house
insects, parasites or diseases. If it has been contaminated with
plant pests it can be sprayed or wiped down with a 5% bleach
solution which kills most organisms. The room must be well-venitalted
when this operation is going on. The room will be subject to high
humidity so any materials such as clothing which might be damaged
by moisture are removed.
Since the plants will be watered, and water may be spilled, the
floors and any other areas that may be water damaged should be
covered with linoleum or plastic. High grade 6 or 8 mil
polyethylene drop cloths or vinyl tarps protect a floor well. The
plastic should be sealed with tape so that no water seeps to the
floor.
The amount of light delivered to the plant rises dramatically
when the space is enclosed by reflective material. Some good
reflective materials are flat white paint, aluminum foil (the
dull side so that the light is diffused), white cardboard,
plywood painted white, white polyethylene, silvered mylar, gift
wrap, white cloth, or silvered plastic such as Astrolon. Mterials
can be taped or tacked onto the walls, or hung as curtains. All
areas of the space should be covered with reflective material.
The walls, ceiling and floors are all capable of reflecting light
and should be covered with reflective material such as aluminum
foil. It is easiest to run the material vertically rather than
horizontally. Experienced growers find it convenient to use the
wide, heavy-duty aluminum foil or insulating foil (sold in wide
rolls) in areas which will not be disturbed and plastic or cloth
curtains where the material will be moved.
Windows can be covered with opaque material if a bright light
emanating from the window would draw suspicion. If the window
does not draw suspicion and allows bright light into the room, it
should be covered with a translucent material such as rice paper,
lace curtains, or aquarium crystal paint.
Garages, metal buildings, or attics can be converted to
lighthouses by replacing the roof with fiberglass greenhouse
material such as Filon. These translucent panels permit almost
all the light to pass through but diffuse it so that there is no
visible image passing out while there is an even distribution of
light coming in. A space with a translucent roof needs no
artificial lighting in the summer and only supplemental lighting
during the other seasons. Overhead light entering from askylight
or large window is very helpful. Light is utilized best if it is
diffused. Concrete and other cold floors should be covered with
insulating material such as foam carpet lining, styrofoam
sheeting, wood planks or wooden palettes so that the plant
containers and the roots are kept from getting cold.
Marijuana Grower's Handbook - Part 6 of 33
"Plant Size and Spacing"
Marijuana varieties differ not only in their growth rate, but
also in their potential size. The grower also plays a role in
determining the size of the plants because the plants can be
induced to flower at any age or size just by regulating the
number of hours of uninterrupted darkness that the plants receive.
Growers have different ideas about how much space each plant
needs. The closer the plants are spaced, the less room the
individual plant has to grow. Some growers use only a few plants
in a space, and they grow the plants in large containers. Other
growers prefer to fill the space with smaller plants. Either
method works, but a garden with smaller plants which fills the
space mroe completely probably yields more in less time. The
total vegetative growth in a room containing many small sized
plants is greater than a room containing only a few plants. Since
each plant is smaller, it needs less time to grow to its desired
size. Remember that the gardener is interested in a crop of
beautiful buds, not beautiful plants. The amount of space a plant
requires depends on the height the plants are to grow. A plant
growing 10 feet high is going to be wider than a 4 foot plant.
The width of the plant also depends on cultivation practices.
Plants which are pruned grow wider than unpruned plants. The
different growth characteristics of the plants also affect the
space required by each plant. In 1- or 2-light gardens, where the
plants are to grow no higher than 6 feet, plants are given
between 1 and 9 square feet of space. In a high greenhouse lit by
natural light, where the plants grow 10-12 feet high, the plants
may be given as much as 80 to 100 square feet.
Marijuana Grower's Handbook - part 7 of 33
"Planting Mixes"
One of the first books written on indoor growing suggested
that the entire floor of a grow room be filled with soil. This
method is effective but unfeasible for most cultivators. Still,
the growers have a wide choice of growing mediums and techniques;
they may choose between growing in soil or using a hydroponic
method.
Most growers prefer to cultivate their plants in containers
filled with soil, commercial mixes, or their own recipe of soil,
fertilizers, and soil conditioners. These mixes vary quite a bit
in their content, nutrient values, texture, pH, and water-holding
capacity. Potting soil is composed of topsoil, which is a natural
outdoor composite high in nutrients. It is the top layer of soil,
containing large amounts of organic material such as humus and
compost as well as minerals and clays. Topsoil is usually
lightened up so that it does not pack. This is done by using sand,
vermiculite, perlite, peat moss and/or gravel. Potting soil tends
to be very heavy, smell earthy and have a rich dark color. It can
supply most of the nutrients that a plant needs for the first
couple of months.
Commercial potting mixes are composites manufactured from
ingredients such as bark or wood fiber, composts, or soil
conditioners such as vermiculite, perlite, and peat moss. They
are designed to support growth of houseplants by holding adequate
amounts of water and nutrients and releasing them slowly. Potting
mixes tend to be low in nutrients and often require fertilization
from the outset. Many of them may be considered hydroponic mixes
because the nutrients are supplied by the gardener in a water
solution on a regular basis.
Texture of the potting mix is the most important consideration
for containerized plants. The mixture should drain well and allow
air to enter empty spaces so that the roots can breathe oxygen.
Mixes which are too fine may become soggy or stick together,
preventing the roots from obtaining the required oxygen. A soggy
condition also promotes the growth of anaerobic bacteria which
release acids that eventually harm the roots. A moist potting mix
with good texture should form a clump if it is squeezed in a fist;
then with a slight poke the clod should break up. If the clod
stays together, soil conditioners are required to loosen it up.
Vermiculite, perlite or pea-sized styrofoam chips will serve the
purpose. Some growers prefer to make their own mixes. These can
be made from soil, soil conditioners, and fertilizers.
Plants grown in soil do not grow as quickly as those in
hydroponic mixes. However, many growers prefer soil for aesthetic
reasons. Good potting mixes can be made from topsoil fairly easy.
Usually it is easier to buy topsoil than to use unpasteurized
topsoil which contains weed seeds, insects and disease organisms.
Outdoors, these organisms are kept in check, for the most part,
by the forces of nature. Bringing them indoors, however, is like
bringing them into an incubator, where many of their natural
enemies are not around to take care of them. Soil can be
sterilized using a 5% bleach solution poured through the medium
or by being steamed for 20 minutes. Probably the easiest way to
sterilize soil is to use a microwave. It is heated until it is
steaming, about 5 minutes for a gallon or more.
Potting soils and potting mixes vary tremendously in composition,
pH and fertility. Most mixes contain only small amounts of soil.
If a package is marked "potting soil", it is usually
made mostly from topsoil. If the soil clumps up it should be
loosened using sand, perlite or styrofoam. One part amendment is
used to 2-3 parts soil. Additives listen in Chart 7-2 may also be
added. Here is a partial list of soil conditioners:
Foam
Foam rubber can be used in place of styrofoam. Although it holds water trapped between its open cells it also holds air. About 1.5 parts of foam rubber for every part of styrofoam is used. Pea-size pieces or smaller should be used.
Gravel
Gravel is often used as a sole medium in hydroponic systems because it is easy to clean, never wears out, does not "lock up" nutrients, and is inexpensive. It is also a good mix ingredient because it creates large spaces for airpockets and gives the mix weight. Some gravel contains limestone (see "Sand"). This material should not be used.
Lava
Lava is a preferred medium on its own or as a part of a mix. It is porous and holds water both on its surface and in the irregular spaces along its irregular shape. Lava is an ideal medium by itself but is sometimes considered a little too dry. To give it moremoisture-holding ability, about one part of wet vermiculite ismixed with 3 to 6 parts lava. The vermiculite will break up and coat the lava, creating a mdeium with excellent water-holding abilities and plenty of air spaces. If the mix is watered from the top, the vermiculite will wash down eventually, but if it is watered from the bottom it will remain.
Perlite
Perlite is an expanded (puffed) volcanic glass. It is lightweight with many peaks and valleys on its surface, where it traps particles of water. However, it does not absorb water into its structure. It does not break down easily and is hard to the touch. Perlite comes in several grades with the coarser grade being better for larger containers. perlite is very dusty when dry. To eliminate dust, the material is watered to saturation with a watering can or hose before it is removed from the bag. Use of masks and respirators is important.
Rockwool
Rockwool is made from stone which has been heated then extruded into think strands which are something like glass wool. It absorbs water like a wick. It usually comes in blocks or rolls. It can be used in all systems but is usually used in conjunction with drop emitters. Growers report phenomenal growth rates using rockwool. It is also very convenient to use. The blocks are placed in position or it is rolled out. Then seeds or transplants are placed on the material.
Sand
Sand is a heavy material which is often added to a mixture to
increase its weight so that the plant is held more firmly. It
promotes drainage and keeps the mix from caking. Sand comes in
several grades too, but all of them seem to work well. The best
sand to use is composed of quartz. Sand is often composed of
limestone; the limestone/sand raised pH, causing micronutrients
to precipitate, making them unavailable to the plants. It is best
not to use it.
Limestone-containing sand can be "cured" by soaking in
a solution of water and superphosphate fertilizer which binds
with the surface of the lime molecule in the sand, making the
molecule temporarily inert. One pound of superphosphate is used
to 5 gallons of water. It dissolves best in hot water. The sand
should sit in this for 6-12 hours and then be rinsed.
Superphosphate can be purchased at most nurseries. Horticultural
sand is composed of inert materials and needs no curing. Sand
must be made free of salt if it came from a salt-water area.
Sphagnum Moss
Sphagnum or peat moss is gathered from bogs in the midwest. It absorbs many times its own weight in water and acts as a buffer for nutrients. Buffers absorb the nutrients and hold large amounts in their chemical structure. The moss releases them gradually as they are used by the plant. If too much nutrient is supplied, the moss will act on it and hold it, preventing toxic buildups in the water solution. Moss tends to be acidic so no more than 20% of the planting mix should be composed of it.
Styrofoam Pellets
Styrofoam is a hydrophobic material (it repels water) and is an excellent soil mix ingredient. It allows air spaces to form in the mix and keeps the materials from clumping, since it does not bond with other materials or with itself. One problem is that it is lighter than water and tends to migrate to the top of the mix. Styrofoam is easily used to adjust the water-holding capacity of a mix. Mixes which are soggy or which hold too much water can be "dried" with the addition of styrofoam. Styrofoam balls or chips no larger than a pea should be used in fine-textured mixtures. Larger styrofoam pieces can be used in coarse mixes.
Vermiculite
Vermiculite is porcessed puffed mica. It is very lightweight but holds large quantities of water in its structure. Vermiculite is available in several size pieces. The large size seems to permit more aeration. Vermiculite breaks down into smaller particles over a period of time. Vermiculite is sold in several grades based on the size of the particles. The fine grades are best suited to small containers. In large containers, fine particles tend to pack too tightly, not leaving enough space for air. Coarser grades should be used in larger containers. Vermiculite is dusty when dry, so it should be wet down before it is used.
Mediums used in smaller containers should be able to absorb more water than mediums in larger containers. For instance, seedlings started in 1 to 2 inch containers can be planted in plain vermiculite or soil. Containers up to about one gallon can be filled with a vermiculite-perlite or soil-perlite mix. Containers larger than that need a mix modified so that it does not hold as much water and does not become soggy. The addition of sand, gravel, or styrofoam accomplishes this very easily. Here are lists of different mediums suitable for planting: Below is a list of the moist mixtures, suitable for the wick system, the reservoir system and drop emitters which are covered in part 9.
Chart 7-1-A: Moist Planting Mixes
Here are some drier mediums suitable for flood systems as well as drip emitters (hydroponic systems covered in part 9).
Chart 7-1-B: Flood System/Drip Emitter Mixes
Manure and other slow-releasing natural
fertilizers are often added to the planting mix.
With these additives, the grower needs to use
ferilizers only supplementally. Some of the
organic amendments are listed in the following
chart. Organic amendments can be mixed but should
not be used in amounts larger than those
recommended because too much nutrient can cause
toxicity.
Some growers add time-release fertilizers to the
mix. These are formulated to release nutrients
over a specified period of time, usually 3, 4, 6
or 8 months. The actual rate of release is
regulated in part by temperature, and since house
temperatures are usually higher than outdoor soil
temperatures, the fertilizers used indoors
release over a shorter period of time than is
noted on the label. Gardeners find that they must
supplement the time-release fertilizer formulas
with soluble fertilizers during the growing
season. Growers can circumvent this problem by
using time-release fertilizer suggested for a
longer period of time than the plant cycle. For
instance, a 9 month time-release fertilizer can
be used in a 6 month garden. Remember that more
fertilizer is releasing faster, so that a larger
amount of nutrients will be available than was
intended. These mixes are used sparingly. About
one tablespoon of dolomite limestone should be
added for each gallon of planting mix, or a half
cup per cubic foot of mix. This supplies the
calcium along with mangesium, both of which the
plants require. If dolomite is unavailable, then
hydrated lime or any agricultural lime can be
used.
Chart 7-2: Organic Amendments
+-----------------+-----+-----+------+-------------------------------------+ | Amendment | N | P | K | 1 Part : X Parts Mix | | Cow Manure | 1.5 | .85 | 1.75 | Excellent condition, breaks down | | | | | | over the growing season. 1:10 | +-----------------+-----+-----+------+-------------------------------------+ | Chicken Manure | 3 | 1.5 | .85 | Fast acting. 1:20 | +-----------------+-----+-----+------+-------------------------------------+ | Blood Meal | 15 | 1.3 | .7 | N quickly available. 1:100 | +-----------------+-----+-----+------+-------------------------------------+ | Dried Blood | 13 | 3 | 0 | Very soluble. 1:100 | +-----------------+-----+-----+------+-------------------------------------+ | Worm Castings | 3 | 1 | .5 | Releases N gradually. 1:15 | +-----------------+-----+-----+------+-------------------------------------+ | Guano | 2-8 | 2-5 | .5-3 | Varies alot, moderately soluble. | | | | | | For guano containing 2% nitrogen, | | | | | | 1:15. For 8% nitrogen, 1:40 | +-----------------+-----+-----+------+-------------------------------------+ | Cottonseed Meal | 6 | 2.5 | 1.5 | Releases N gradually. 1:30. | +-----------------+-----+-----+------+-------------------------------------+ | Greensand | 0 | 1.5 | 5 | High in micronutrients. Nutrients | | | | | | available over the season. 1:30 | +-----------------+-----+-----+------+-------------------------------------+ | Feathers | 15 | ? | ? | Breaks down slowly. 1:75 | +-----------------+-----+-----+------+-------------------------------------+ | Hair | 17 | ? | ? | Breaks down slowly. 1:75 |
N = Nitrogen * P = Phosphorous * K = Potassium
Marijuana Grower's Handbook - part 8 of 33
"Hydroponics vs. Soil Gardening"
Plants growing in the wild outdoors obtain
their nutrients from the breakdown of complex
organic chemicals into simpler water-soluble
forms. The roots catch the chemicals using a
combination of electrical charges and chemical
manipulation. The ecosystem is generally self-supporting.
For instance, in some tropical areas most of the
nutrients are actually held by living plants. As
soon as the vegetation dies, bacteria and other
microlife feast and render the nutrients water-soluble.
They are absorbed into the soil and are almost
immediately taken up by higher living plants.
Farmers remove some of the nutrients from the
soil when they harvest their crops. In order to
replace those nutrients they add fertilizers and
other soil additives. [pH : perhaps shake would
be good fertilizer for one's next crop]
Gardeners growing plants in containers have a
closed ecology system. Once the plants use the
nutrients in the medium, their growth and health
is curtailed until more nutrients become
available to them. It is up to the grower to
supply the nutrients required by the plants. The
addition of organic matter such as compost or
manure to the medium allows the plant to obtain
nutrients for a while without the use of water-soluble
fertilizers. However, once these nutrients are
used up, growers usually add water-soluble
nutrients when they water. Without realizing it,
they are gardening hydroponically. Hydroponics is
the art of growing plants, usually without soil,
using water-soluble fertilizers as the main or
sole source of nutrients. The plants are grown in
a non-nutritive medium such as gravel or sand or
in lightweight materials such as perlite,
vermiculite or styrofoam. The advantages of a
hydroponic system over conventional horticultural
methods are numerous: dry dpots, root drowning
and soggy conditions do not occur. Nutrient and
pH problems are largely eliminated since the
grower maintains tight control over their
concentration; there is little chance of "lockup"
which occurs when the nutrients are fixed in the
soil and unavailable to the plant; plants can be
grown more conveniently in small containers; and
owing to the fact that there is no messing around
with soil, the whole operation is easier, cleaner,
and much less bothersome than when using
conventional growing techniques.
Marijuana Grower's Handbook - part 9 of 33
"Hydroponic Systems"
Most hydroponic systems fall into one of two broad categories: passive or active. Passive systems such as reservoir or wick setups depend on the molecular action inherent in the wick or medium to make water available to the plant. Active systems which include the flood, recirculating drop and aerated water systems, use a pump to send nourishment to the plants. Most commercially made "hobby" hydroponic systems designed for general use are shallow and wide, so that an intensive garden with a variety of plants can be grown. But most marijuana growers prefer to grow each plant in an individual container.
PASSIVE HYDROPONIC SYSTEMS
The Wick System
The wick system is inexpensive, easy to set up
and easy to maintain. The principle behind this
type of passive system is that a length of 3/8 to
5/8 inch thick braided nylon rope, used as a wick,
will draw water up to the medium and keep it
moist. The container, which can be an ordinary
nursery pot, holds a rooting medium and has wicks
runing along the bottom, drooping through the
holes at the bottom, reaching down into a
reservoir. Keeping the holes in the container
small makes it difficult for roots to pentrate to
the reservoir. The amount of water delivered to
the medium can be increased by increasing the
number, length, or diameter of the wicks in
contact with the medium.
A 1 gallon container needs only a single wick, a
three gallon container should have two wicks, a
five gallon container, three wicks. The wick
system is self regulating; the amount of water
delivered depnds on the amount lost through
evaporation or transpiration. Each medium has a
maximum saturation level. Beyond that point, an
increase in the number of wicks will not increase
the moisture level. A 1-1-1 combination of
vermiculite, perlite, and styrofoam is a
convenient medium because the components are
lightweight and readily available. Some
commercial units are supplied with coarse
vermiculite. To increase weight so that the plant
will not tip the container over when it gets
large, some of the perlite in the recipe can be
replaced with sand. The bottom inch or two of the
container should be filled only with vermiculite,
which is very absorbent, so that the wicks have a
good medium for moisture transfer. Wick systems
are easy to construct. The wick should extend 5
inches or more down from the container. Two
bricks, blocks of wood, or styrofoam are placed
on the bottom of a deep tray (a plastic tray or
oil drip pan will do fine.) Then the container is
placed on the blocks so that the wicks are
touching the bottom of the tray. The tray is
filled with a nutrient/water solution. Water is
replaced in the tray as it evaporates or is
absorbed by the medium through the wick.
A variation of this system can be constructed
using an additional outer container rather than a
tray. With this method less water is lost due to
evaporation.
To make sure that the containers git together and
come apart easily, bricks or wood blocks are
placed in the bottom of the outer container. The
container is filled with the nutrient/water
solution until the water comes to just below the
bottom of the inner container. Automating this
system is simple to do. Each of the tray or
bottom containers is connected by tubing to a
bucket containing a float valve such as found in
toilets. The valve is adjusted so that it shuts
off when the water reaches a height about 1/2
inch below the bottom of the growing containers.
The bucket with the float valve is connected to a
large reservoir such as a plastic garbage can or
55 gallon drum. Holes can be drilled in the
containers to accomodate the tubing required, or
the tubes can be inserted from the top of the
containers or trays. The tubes should be secured
or weighted down so that they do not slip out and
cause floods. The automated wick system works as
a siphon. To get it started, the valve container
is primed and raised above the level of the
individual trays. Water flows from the valve to
the plant trays as a result of gravity. Once the
containers have filled and displaced air from the
tubes, the water is automatically siphoned and
the valve container can be lowers. Each container
receives water as it needs it. A simpler system
can be devised by using a plastic kiddie pool and
some 4x4's or a woodem pallet. Wood is placed in
the pool so that the pots sit firmly on the board;
the pool is then filled with water up to the
bottom of the pots. The wicks move the water to
the pots. Wick systems and automated wick systems
are available from several manufacturers. Because
they require no moving parts, they are generally
reliable although much more expensive than
homemande ones, which are very simple to make.
Wick system units can be filled with any of the
mixes found in Chart 7-1-A.
The Reservoir System
The reservoir system is even less complex than the wick system. For this setup all a grower needs to do is fill the bottom 2 or 3 inches of a 12 inch deep container with a coarse, porous, inert medium such as lava, ceramic beads or chopped unglazed pottery. The remaining portion is filled with one of the mixes containing styrofoam. The container is placed in a tray, and sits directly in a nutrient-water solution 2-3 inches deep. The system is automated by placing the containers in a trough or large tray. Kiddie pools can also be used. The water is not replaced until the holding tray dies. Passive systems should be watered from the top down once a month so that any buildup of nutrient salts caused by evaporation gets washed back to the bottom.
ACTIVE HYDROPONIC SYSTEMS
Active systems move the water using mechanical devices in order to deliver it to the plants. There are many variations on active systems but most of them fall into one of three categories: flood systems, drip systems, or nutrient film systems.
The Flood System
The flood system is the type of unit that most
people think of when hydroponics is mentioned.
The system usually has a reservoir which
periodically empties to flood the container or
tub holding the medium. The medium holds enough
moisture between irrigations to meet the needs of
the plant. Older commercial greenhouses using
this method often held long troughs or beds of
gravel. Today, flood systems are designed using
individual containers. Each container is attached
to the reservoir using tubing.
A simple flood system can be constructed using a
container with a tube attached at the bottom of a
plastic container [pH: that which the plant is
placed in] and a jug. The tube should reach down
to the jug, which should be placed below the
bottom of the growing container. To water, the
tube is held above the container so that it doesn't
drop. The water is poured from the jug into the
container. Next, the tube is placed in the jug
and put back into position, below the growing
container. The water will drain back into the jug.
Of course, not as much will drain back in as was
poured out. Some of the water was retained in the
growing unit. Automating this unit is not
difficult. A two-holed stopper is placed in the
jug. A tube from the growing unit should reach
the bottom of the reservoir container. Another
tube should be attached to the other stopper hole
and then to a small aquarium-type air pump which
is regulated by a timer. When the pump turns on,
it pushes air into the jug, forcing the water
into the container. When the pump goes off, the
water is forced back into the jug by gravity.
Several growing units can be hooked up to a large
central reservoir and pump to make a large system.
The water loss can automatically be replaced
using a float valve, similar to the ones used to
regulate water in a toilet. Some growers place a
second tube near the top of the container which
they use as an overflow drain. Another system
uses a reservoir above the growing container
level. A water timing valve or solenoid valve
keeps the water in the reservoir most of the time.
When the valve opens, the water fills the growing
containers as well as a central chamber which are
both at the same height. The growing chambers and
the central chamber are attached to each other.
The water level is regulated by a float valve and
a sump pump. When the water level reaches a
certain height, near the top of the pots, the
sump pump automatically turns on and the water is
pumped back up to the reservoir. One grower used
a kiddie pool, timer valve, flower pots, a raised
reservoir and a sump pump. He placed the
containers in the kiddie pool along with the sump
pump and a float valve. When the timer valve
opened, the water rushed from the tank to the
kiddie pool, flooding the containers. The pump
turned on when the water was two inches from the
top of the containers and emptied the pool. Only
when the valve reopened did the plants receive
more water.
With this system, growers have a choice of
mediums, including sand, gravel, lava, foam or
chopped-up rubber. Vermiculite, perlite, and
styrofoam are too light to use. The styrofoam and
perlite float, and the vermiculite becomes too
soggy.
The plants' water needs to increase during the
lighted part of the daily cycle, so the best time
to water is as the light cycle begins. If the
medium does not hold enough moisture between
waterings, the frequency of waterings is
increased.
There are a number of companies which manufacture
flood systems. Most of the commercially made ones
work well, but they tend to be on the expensive
side. They are convenient, though.
The Drip System
Years ago, the most sophisticated commercial greenhouses used drip emitter systems which were considered exotic and sophisticated engineering feats. These days, gardeners can go to any well-equipped nursery and find all of the materials necessary to design and build the most sophisticated drop systems. These units consist of tubing and emitters which regulate the amount of water delivered to each individual container. Several types of systems can be designed using these devices. The easiest system to make is a non-return drain unit. The plants are watered periodically using a diluted nutrient solution. Excess water drains from the containers and out of the system. This system is only practical when there is a drain in the growing area. If each container has a growing tray to catch excess water and the water control valve is adjusted closely, any excess water can be held in the tray and eventually used by the plant or evaporated. Once a gardener gets the hang of it, matching the amount of water delivered to the amount needed is easy to do. One grower developed a drip emitter system which re-uses water by building a wooden frame using 2x4's and covering it with corrugated plastic sheeting. She designed it so that there was a slight slope. The containers were placed on the corrugated plastic, so the water drained along the corrugations into a rain drainage trough, which drained into a 2 or 3 gallon holding tank. The water was pumped from the holding taink back to the reservoir. The water was released from the reservoir using a timer valve.
Aerated Water
The aerated water system is probably the most complex of the hydroponic systems because it allows for the least margin of error. It should only be used by growers with previous hydroponic experience. The idea of the system is that the plant can grow in water as long as the roots receive adequate amounts of oxygen. To provide the oxygen, an air pump is used to oxygenate the water through bubbling and also by increasing the circulation of the water so that there is more contact with air. The plants can be grown in individual containers, each with its own bubbler or in a single flooded unit in which containers are placed. One grower used a vinyl covered tank he constructed. He placed individual containers that he made into the tank. His containers were made of heavy-duty nylon mesh used by beermakers for soaking hops. This did not prevent water from circulating around the roots. Aerated water systems are easy to build. A small aquarium air pump supplies all the water that is required. An aerator should be connected to the end and a clear channel made in the container for the air. The air channel allows the air to circulate and not disturb the roots. Gravel, lava, or ceramic is used.
Nutrient Film Technique
The nutrient film technique is so named because the system creates a film of water that is constantly moving around the roots. This technique is used in many commercial greenhouses to cultivate fast growing vegetables such as lettuce without any medium. The plants are supported by collars which hold them in place. This method is unfeasible for marijuana growers. However, it can be modified a bit to create an easy-to-care-for garden. Nursery suppliers sell water mats, which disperse water from a soaker hose to a nylon mat. The plants grow in the bottomless containers which sit on the mat. The medium absorbs water directly from the mat. In order to hold the medium in place, it is placed in a nylon net bag in the container.
Marijuana Grower's Handbook - part 10 of 33
"Growing in the Ground"
Some growers have the opportunity to grow
plants directly in the ground. Many greenhouses
are built directly over the earth. Growing
directly in the soil has many advantages over
container growing. A considerable amount of labor
may be eliminated because there is no need to
prepare labor-intensive containers with expensive
medium. Another advantage is that the plants'
needs are met more easily.
Before using any greenhouse soil, it is necessary
to test it. The pH and fertility of soils vary so
much that there are few generalizations that can
be made about them.
The most important quality of any soil is its
texture. Soils which drain well usually are
composed of particles of varying size. This
creates paths for water to flow and also allows
airs pockets to remain even when the soil is
saturated.
Soils composed of very fine particles, such as
mucks and clay, do not drain well. Few air
particles are trapped in these soils when they
are saturated. When this happens, the roots are
unable to obtain oxygen and they weaken when they
are attacked by anaerobic bacteria. These soils
should be adjusted with sand and organic matter
which help give the medium some porosity.
Materials suitable for this include sand, compost,
composted manure, as well as perlite, lava,
gravel, sphagnum moss, styrofoam particles and
foam particles.
Low lying areas may have a very high water table
so that the soils remain saturated most of the
time. One way to deal with this problem is to
create a series of mounds or raised beds so that
the roots are in ground at higher level than the
floor level.
Once soil nutrient values are determined,
adjustments can be made in the soil's fertility.
For marijuana, the soil should test high in total
Nitrogen, and the medium should test high in
Phosphorous and Potassium. This is covered in
subsequent files.
Growers use several methods to prepare the soil.
Some prefer to till the whole area using either a
fork, a roto-tiller or a small tractor and plow.
The marijuana plant grows both vertical and
horizontal roots. The horizontal roots grow from
the surface to a depth of 9-18 inches depending
on the soil's moisture. They grow closer to the
surface of moist soils. The vertical root can
stretch down several feet in search of water. In
moist soils, the vertical roots may be short,
even stunted. Soil with loose texture, sandy
soils, and soils high in organic matter may have
adequate aeration, porosity, and space for roots
and may not have to be tilled at all. Most soils
should be dug to a depth of 6-9 inches. The
tighter the soil's texture, the deeper it should
be filled. If the soil is compacted, it is dug to
a depth of two feet. This can be done by plowing
and moving the soil in alternate rows and then
plowing the newly uncovered soil. Soil texture
adjustors such as gypsum are added to the bottom
layer of the soil as well as the top layer, but
soil amendments such as fertilizers or compst are
added only to the top layer, where most of the
plant's roots are. Then the soil is moved back
into the troughs and the alternate rows are
prepared the same way. A variation of this
technique is the raised bed. First, the whole
area is turned, and then aisles are constructed
by digging out the pathways and adding the
material to the beds. With the addition of
organic soil amendments, the total depth of
prepared soil may stretch down 18 inches. Some
growers use planting holes rather than tilling
the soil. A hole ranging between 1 and 3 feet
wide and 1.5 and 3 feet deep is dug at each space
where there is to be a plant. The digging can be
facilitated using a post hole digger, electric
shovel, or even a small backhoe or power hole
digger. Once the hole is dug the soil is adjusted
with amendments or even replaced with a mix.
No matter how the soil is prepared, the
groundwater level and the permeability of the
lower layers is of utmost importance. Areas with
high water tables, or underlying clay or hardpan
will not drain well. In either case the harden
should be grown in raised beds which allow
drainage through the aisles and out of the
growing area, rather than relying on downward
movement through soil layers.
Soils in used greenhouses may be quite imbalanced
even if the plants were growing in containers.
The soil may have a buildup of mutrient salts,
either from runoff or direct application, and
pesticides and herbicides may be present. In
soils with high water tables, the nutrients and
chemicals have nowhere to go, so they dissolve
and spread out horizontally as well as vertically,
contaminating the soil in surrounding areas.
Excess salts can be flushed from the soil by
flooding the area with water and letting it drain
to the water table. In areas with high water
tables, flushing is much more difficult. Trenches
are dug around the perimeter of the garden which
is then flooded with nutrient-free water. As the
water drains into the trenches, it is removed
with a pump and transported to another location.
Pesticides and herbicides may be much mroe
difficult to remove. Soils contaminated with
significant amounts of residues may be unsuitable
for use with material to be ingested or inhaled.
Instead, the garden should be grown in containers
using nonindigenous materials. Usually plants are
sexed before they are planted into the ground. If
the soil showed adequate nutrient values no
fertilizer or side dressing will be required for
several months.
Several growers have used ingenious techniqures
to provide their gardens with earthy environments.
One grower in Oregon chopped through the concrete
floor of his garage to make planting holes. The
concrete had been poured over sub-soil so he dug
out the holes and replaced the sub-soil with a
mixture of composted manure, vermiculite, perlite,
worm castings, and other organic ingredients. He
has been using the holes for several years. After
several crops, he redigs the holes and adds new
ingredients to the mix. A grower in Philadelphia
lived in a house with a backyard which was
cemented over. He constructed a raised bed over
the concrete using railroad ties and filled it
with a rich topsoil and composted manure mixture,
then built his greenhouse over that. The growing
bed is about 15 inches deep and the grower
reports incredible growth rates.
Marijuana Grower's Handbook - part 11 of 33
"Lighting and Lights"
Green plants use light for several purposes.
The most amazing thing that they can do with it
is to use the energy contained in light to make
sugar from water and carbon dioxide. This process
is called photosynthesis and it provides the
basic building block for most life on Earth.
Plants convert the sugars they make into starches
and then into complex molecules composed of
starches, such as cellulose. Amino acids, the
building blocks of all proteins, are formed with
the addition of nitrogen atoms. Plants also use
ligh to regulate their other life processes. As
we mentioned earlier, marijuana regulates its
flowering based on the number of hours of
uniterrupted darkness. (See part 25, Flowering)
Sunlight is seen as white light, but is composed
of a broadf band of colors which cover the optic
spectrum. Plants use red and blue light most
efficiently for photosynthesis and to regulate
other processes. However, they do use other light
colors as well for photosynthesis. In fact, they
use every color except green, which they reflect
back. (That is why plants appear green; they
absorb all the other spectrums except green.) In
controlled experiements, plants respond more to
the toal amount of light received than to the
spectrums in which it was delivered. The best
source of light is the sun. It requires no
expense, no electricity, and does not draw
suspicion. It is brighter than artifical light
and is self regulating. Gardeners can use the sun
as a primary source of light if they have a large
window, skylight, translucent roof, enclosed
patio, roof garden, or greenhouse. These gardens
may require some supplemental lightning,
especially if the light enters from a small area
such as a skylight, in order to fill a large area.
It is hard to say just how much supplemental
light a garden needs. Bright spaces which are lit
from unobstructed overhead light such as a
greenhouse or a large southern window need no
light during the summer but may need artificial
light during the winter to supplement the weak
sunlight or overcast conditions. Spaces receiving
indirect sunlight during the summer may need some
supplemental lighting. Light requirements vary by
variety. During the growth cycle, most varieties
will do well with 1000-1500 lumens per square
foot although the plants can usemore lumens, up
to 3000, efficiently. Equatorial varieties may
develop long internodes (spaces on the stem
between the leaves) when grown under less that
bright conditions. During flowering, indica
varieties can mature well on 2000 lumens.
Equatorial varieties require 2500-5000 lumens.
Indica-sativa F1 (first generation) hybrids
usually do well on 2500-3000 lumens.
Some light meters have a foot-candle readout.
Thirty-five millimeter cameras that have built-in
light meters can also be used. In either case, a
sheet of white paper is placed at the point to be
measured so it reflects the light most
brilliantly. Then the meter is focused entirely
on the paper.
The camera is set for ASA 100 film and the
shutter is set for 1/60 second. A 50 mm or "normal"
lens is used. Using the manual mode, the camera
is adjusted to the correct f-stop. The conversion
chart, 10-1, shows the amount of light hitting
the paper.
Most growers, for one reason or another, are not
able to use natural light to grow marijuana.
Instead, they use artificial lights to provide
the light energy which plants require to
photosynthesize, regulate their metabolism, and
ultimately to grow. There are a number of sources
of artificial lighting. Cultivators rarely use
incandescent or quartz halogen lights. They
convert only about 10% of the energy they use to
light and are considered inefficient.
Chart 10-1: Footcandles
+----------------------+----------------------+
| 1/60 Second, ASA 100 | 1/125 Second ASA 100 |
+--------+-------------+--------+-------------+
| F-Stop | Footcandles | F-Stop | Footcandles |
+--------+-------------+--------+-------------+
| f.4 | 64 | f.4 | 128 |
+--------+-------------+--------+-------------+
| f.5.6 | 125 | f.5.6 | 250 |
+--------+-------------+--------+-------------+
| f.8 | 250 | f.8 | 500 |
+--------+-------------+--------+-------------+
| f.11 | 500 | f.11 | 1000 |
+--------+-------------+--------+-------------+
| f.16 | 1000 | f.16 | 2000 |
+--------+-------------+--------+-------------+
| f.22 | 2000 | f.22 | 4000 |
+--------+-------------+--------+-------------+
On some cameras it is easier to adjust the shutter speed, keeping the f.stop set at f.4 (at ASA 100):
+----------------+-------------+
| Shutter Speed | Footcandles |
+----------------+-------------+
| 1/60 | 64 |
+----------------+-------------+
| 1/125 | 125 |
+----------------+-------------+
| 1/250 | 250 |
+----------------+-------------+
| 1/500 | 500 |
+----------------+-------------+
| 1/1000 | 1000 |
+----------------+-------------+
| 1/2000 | 2000 |
+----------------+-------------+
FLUORESCENT TUBES
Growers have used flurorescent tubes to
provide light for many years. They are
inexpensive, are easy to set up, and are very
effective. Plants grow and bud well under them.
They are two to three times as efficient as
incandescents. Until recently, fluorescents came
mostly in straight lengths of 2, 4, 6, or 8 feet,
which were placed in standard reflectors. Now
there are many more options for the fluorescent
user. One of the most convenient fixtures to use
is the screw-in converter for use in incandescent
sockets, which come with 8 or 12 inch diameter
circular fluorescent tubes. A U-shaped 9 inch
screw-in fluorecent is also available. Another
convenient fixture is the "light wand",
which is a 4 foot, very portable tube. It is not
saddled with a cumbersome reflector. Fluorescents
come in various spectrums as determined by the
type of phosphor with which the surface of the
tube is coated. Each phosphor emits a different
set of colors. Each tube has a spectrum
identification such as "warm white",
"cool white", "daylight", or
"deluxe cool white" to name a few. This
signifies the kind of light the tube produces.
For best results, growers use a mixture of tubes
which have various shades of white light. Once
company manufactures a fluorescent tube which is
supposed to reproduce the sun's spectrum. It is
called the Vita-Lite and works well. it comes in
a more efficient version, the "Power Twist",
which uses the same amount of electricity but
emits more light because it has a larger surface
area. "Gro-Tubes" do not work as well
as regular fluorescents even though they produce
light mainly in the red and blue spectrums. They
produce a lot less light than the other tubes.
To maintain a fast growing garden, a minimum of
20 watts of fluorescent light per square foot is
required. As long as the plants' other needs are
met, the more light that the plants receive, the
faster and bushier they will grow. The plants'
buds will also be heavier and more developed.
Standard straight-tubed fluorescent lamps use 8-10
watts per linear foot. To light a garden, 2 tubes
are required for each foot of width. The 8 inch
diameter circular tubes use 22 watts, the 12 inch
diameter use 32 watts. Using straight tubes, it
is possible to fit no more than 4 tubes in each
foot of width because of the size of the tubes. A
unit using a combination of 8 and 12 inch
circular tubes has an input of 54 watts per
square foot. Some companies manufacture energy-saving
electronic ballasts designed for use with special
fluorescent tubes. These units use 39% less
electricity and emit 91% of the light of standard
tubes. For instance, an Optimizer warm light
white 4 foot tube uses 28 watts and emits 2475
lumens. Both standard and VHO ballasts
manufactured before 1980 are not recommended.
They were insulated using carcinogenic PCB's and
they are a danger to your health should they leak.
The shape of the fluorescent reflector used
determines, to a great extent, how much light the
plants receive. Fluorescent tubes emit light from
their entire surface so that some of the light is
directed at the reflector surfaces. Many fixtures
place the tubes very close to each other so that
only about 40% of the light is actually
transmitted out of the unit. The rest of it is
trapped between the tubes or between the tubes
and the reflector. This light may as well not be
emitted since it is doing no good. A better
reflector can be constructed using a wooden frame.
Place the tube holders at equal distances from
each other at least 4 inches apart. This leaves
enough space to construct small mini-reflectors
which are angled to reflect the light downward
and to seperate the light from the different
tubes so that it is not lost in crosscurrents.
These mini-reflectors can be made from cardboard
or plywood painted white. The units should be no
longer than 2.5 feet wide so that they can be
manipulated easily. Larger units are hard to move
up and down and they make access to the garden
difficult, especially when the plants are small,
and there is not much vertical space. The frame
of the reflector should be covered with
reflective material such as aluminum foil so that
all of the light is directed to the garden.
Fluorescent lights should be placed about 2-4
inches from the tops of the plants.
[pH:in Ed's diagram, the reflectors between the
lights have a shape similar to this:
* *
* *
* *
* *
*
Sort of a curving V, if you see what I mean.]
Growers sometimes use fluorescent lights in innovative ways to supplement the main source of the light. Lights are sometimes placed along the sides of the garden or in the midst of it. One grower used light wands which he hung vertically in the midst of the garden. This unit provided light to the lower parts of the plant which are often shaded. Another grower hung a tube horizontally at plant level between each row. He used no reflector because the tube shined on the plants from ever angle. Lights can be hung at diagonal angles to match the different plants' heights.
VERY HIGH OUTPUT (VHO) FLUORESCENTS
Standard fluorescents use about 10 watts per
linear foot - a 4 foot fluorescent uses 40 watts,
an 8 footer 72 watts. VHO tubes use about three
times the electricity that standard tubes use, or
about 215 watts for an 8 foot tube, and they emit
about 2.5 times the light. While they are not
quite as efficient as a standard tube, they are
often more convenient to use. Two tubes per foot
produce the equivalent electricity of 5 standard
tubes. [pH:That's what he says. Why one would
want the tubes to produce electricity instead of
light I will never know.] Only one tube per foot
is needed and two tubes emit a very bright light.
The banks of tubes are eliminated.
VHO tubes come in the same spectrums as standards.
They require different ballasts than standards
and are available at commercial lighting
companies.
METAL HALIDE LAMPS
Metal halide lamps are probably the most
popular lamp used for growing. These are the same
type of lamp that are used outdoors as
streetlamps or to illuminate sports events. They
emit a white light. Metal halide lamps are very
convenient to use. They come ready to plug in.
The complete unit consists of a lamp (bulb),
fixture (reflector) and long cord which plungs
into a remote ballast. The fixture and lamp are
lightweight and are easy to hang. Only one chain
or rope is needed to suspend the fixture, which
take up little space, making it easy to gain
access to the garden. In an unpublished,
controlled experiment, it was observed that
marijuana plants responded better to light if the
light came from a single point source such as a
metal halide, rather than from emissions from a
broad area as with fluorescents. Plants growing
under metal halides develop quickly into strong
plants. Flowering is profuse, with heavier
budding than under fluroescents. Lower leaf
development was better too, because the light
penetrated the top leaves more.
Metal halide lamps are hung in two configurations:
veritcal and horizontal. The horizontal lamp
focuses a higher percent of light on the garden,
but it emits 10% less light. Most manufacturers
and distributors sell verically hanging metal
halides. However, it is worth the effort to find
a horizontal unit.
In order for a vertical hanging metal halide lamp
to deliver light to the garden efficiently, the
horizontal light that is emitting must be
directed downward or the halide must be placed in
the midst of the garden. It only becomes
practical to remove the reflector and let the
horizontally directed light radiate when the
plants have grown a minimum of six feet tall.
Reflectors for vertical lamps should be at least
as long as the lamp. If a reflector does not
cover the lamp completely, some of the light will
be lost horizontally. Many firms sell kits with
reflectors which do not cover the whole lamp.
Reflectors can be modified using thin guage wire
such as poultry wire and aluminum foil. A hole is
cut out in the middle of the chicken wire frame
so that it fits over the wide end of the
reflector. Then it is shaped so that it will
distribute the light as evenly as possible.
Aluminum foil is placed over the poultry wire. (One
grower made an outer frame of 1 x 2's which held
the poultry wire, metal halide, and foil). Metal
halide lamps come in 400, 1000, and 1500 watt
sizes. The 1500 watt lamps are not recommended
because they have a much shorter life than the
other lamps. The 400 watt lamps can easily
illuminate a small garden 5 x 5 feet or smaller.
These are ideal lights for a small garden. They
are also good to brighten up dark spots in the
garden. In European nurseries, 400 watt
horizontal units are standard. They are attached
to the ceiling and placed at even 5 foot
intervals so that light from several lamps hits
each plant. Each lamp beam diffuses as the
vertical distance from the plants may be 6-8 feet,
but no light is lost. The beams overlap. No
shuttle type device is required. The same method
can be used with horizontal 1000 watt lamps and 8
foot intervals. Vertical space should be at least
12 feet.
HIGH PRESSURE SODIUM VAPOR LAMPS
Sodium vapor lamps emit an orange or amber-looking
light. They are the steet lamps that are commonly
used these days. These lights look peculiar
because they emit a spectrum that is heavily
concentrated in the yellow, orange, and red
spectrums with only a small amount of blue. They
produce about 15% more light than metal halides.
They use the same configuration as metal halides:
lamp, reflector, and remote ballast. Growers
originally used single sodium vapor lamps
primarily for flowering because they thought that
if the extra yellow and orange light was closer
to the sun's spectrum in the fall, when the
amount of blue light reaching Earth was limited,
the red light would increase flowering or resin
production. In another unpublished controlled
experiment, a metal halide lamp and a sodium
vapor lamp were used as the only sources of light
in 2 different systems. The garden under the
metal halide matured about a week faster than the
garden under the sodium vapors. Resin content
seemed about the same. Other growers have
reported different results. They claim that the
sodium vapor does increase THC and resin
production. Plants can be grown under sodium
vapor lights as the sole source of illumination.
Many growers use sodium vapor lamps in
conjunction with metal halides; a typical ratio
is 2 halides to 1 sodium. Some growers use metal
halides during the growth stages but change to
sodium vapor lamps during the harvest cycle. This
is not hard to do since both lamps fit in the
same reflector. The lamps use different ballasts.
High pressure sodium vapor lamps come in 400 and
100 watt configurations with remote ballasts
designed specifically for cultivation. Smaller
wattages designed for outdoor illumination are
available from hardware stores. The small wattage
lamps can be used for brightening dark areas of
the garden or for hanging between the rows of
plants in order to provide bright light below the
tops.
ACCESSORIES
One of the most innovative accessories for lighting is the "Solar Shuttle" and its copies. This device moves a metal halide or sodium vapor lamp across a track 6 feet or longer. Because the lamp is moving, each plant comes directly under its field several times during the growing period. Instead of plants in the center receiving more light than those on the edge, the light is more equally distributed. This type of unit increases the total efficiency of the garden. Garden space can be increased by 15-20% or the lamp can be used to give the existing garden more light. Other units move the lamps over an arc path. The units take various amounts of time to complete a journey - from 40 seconds upward.
ELECTRICITY AND LIGHTING
At 110-120 volts, a 1000 watt lamp uses about 8.7 amps (watts divided by volts equals amps). Including a 15% margin for safety it can be figured as 10 amps. Many household circuits are rated for 20 or 30 amps. Running 2 lights on a twenty amp circuit taxes it to capacity and is dangerous. If more electricity is required than can be safely supplied on a circuit, new wiring can be installed from the fusebox. All electrical equipment should be grounded. Some growers report that the electrical company's interest was aroused, sometimes innocently, when their electric bill began to spurt. After all, each hour a lamp is on it uses about 1 kilowatt hour.
Marijuana Grower's Handbook - part 12 of 33
"Carbon Dioxide"
Carbon dioxide (CO2) is a gas which comprises
about .03% (or 300 parts per million, "PPM")
of the atmosphere. It is not dangerous. it is one
of the basic raw materials (water is the other)
required for photosynthesis. The plant makes a
sugar molecule using light for energy, CO2 which
is pulled out of the air, and water, which is
pulled up from its roots. Scientists belive that
early in the Earth's history the atmosphere
contained many times the amount of CO2 it does
today. Plants have never lost their ability to
process gas at these high rates. In fact, with
the Earth's present atmosphere, plant growth is
limited. When plants are growing in an enclosed
area, there is a limited amount of CO2 for them
to use. When the CO2 is used up, the plant's
photosynthesis stops. Only as more CO2 is
provided can the plant use light to continue the
process. Adequate amounts of CO2 may be easily
replaced in well-ventilated areas, but increasing
the amount of CO2 to .2% (2000 PPM) or 6 times
the amount usually found in the atmosphere, can
increase growth rate by up to 5 times. For this
reason, many commercial nurseries provide a CO2
enriched area for their plants.
Luckily, CO2 can be supplied cheaply. At the most
organic level, there are many metabolic processes
that create CO2. For example, organic gardeners
sometimes make compost in the greenhouse. About 1/6
to 1/4 of the pile's starting wet weight is
converted to CO2 so that a 200 pound pile
contributes 33-50 pounds of carbon to the gas.
Carbon makes up about 27% of the weight and
volume of the gas and oxygen makes up 73%, so
that the total amount of CO2 created is 122 to
185 pounds produced over a 30 day period. Brewers
and vintners would do well to ferment their
beverages in the greenhouse. Yeast eat the sugars
contained in the fermentation mix, released CO2
anf alcohol. The yeast produce quite a bit of CO2,
when they are active.
One grower living in a rural area has some rabbit
hutches in his greenhouse. The rabbits use the
oxygen produced by the plants, and in return,
release CO2 by breathing. Another grower told me
that he is supplying his plants with CO2 by
spraying them periodically with seltzer (salt-free
soda water), which is water with CO2 dissolved.
He claims to double the plants' growth rate. This
method is a bit expensive when the plants are
large, but economical when they are small. A
correspondent used the exhausts from his gas-fired
water heater and clothes dryer. To make the area
safe of toxic fumes that might be in the exhaust,
he built a manually operated shut-off valve so
that the spent air could be directed into the
growing chamber or up a flue. Before he entered
the room he sent any exhausts up the flue and
turned on a ventilating fan which drew air out of
the room.
Growers do not have to become brewers, rabbit
farmers, or spray their plants with Canada Dry.
There are several economical and convenient ways
to give the plants adequate amounts of CO2: using
a CO2 generator, which burns natural gas or
kerosene, using a CO2 tank with regulator, or by
evaporating dry ice.
To find out how much CO2 is needed to bring the
growing area to the ideal 2000 PPM, multiply the
cubic area of the growing room (length x width x
height) by .002. The total represents the number
of square feet of gas required to reach optimum
CO2 range. For instance, a room 13' x 18' x 12'
contains 2808 cubic feet: 2808 x .002 equals 5.6
cubic feet of CO2 required. The easiest way to
supply the gas is to use a CO2 tank. All the
equipment can be built from parts available at a
welding suspply store or purchased totally
assembled from many growing supply companies.
Usually tanks come in 20 and 50 pound sizes, and
can be bought or rented. A tank which holds 50
pounds has a gross weight of 170 pounds when
filled.
A grow room of 500 cubic feet requires 1 cubic foot of CO2 A grow room of 1000 cubic feet requires 2 cubic feet of CO2 A grow room of 5000 cubic feet requires 10 cubic feet of CO2 A grow room of 10,000 cubic feet requires 20 cubic feet of CO2
To regulate dispersal of the gas, a combination flow meter/regulator is required. Together they regulate the flow between 10 and 50 cubic feet per hour. The regulator standardizes the pressure and regulates the number of cubic feet released per hour. A solenoid valve shuts the flow meter on and off as regulated by a multicycle timer, so the valve can be turned on and off several times each day. If the growing room is small, a short-range timer is needed. Most timers are calibrated in 1/2 hour increments, but a short-range timer keeps the valve open only a few minutes. To find out how long the valve should remain open, the numberof cubic feet of gas required (in our example 5.6 feet) is divided by the flow rate. For instance, if the flow rate is 10 cubic feet per hour, 5.6 divided by 10
3/5ths ounce provides 1 cubic foot of CO2 1.2 ounces produce 2 cubic feet of CO2 3 ounces produce 5 cubic feet of CO2 6 ounces produce 10 cubic feet of CO2
To find out fuel usage, divide the number of
BTU's produced by 21,800. If a generator produces
12,000 BTU's an hour, it is using 12,000 divided
by 21,800 or about .55 pounds of fuel per hour.
However only .21 pounds are needed. To calculate
the number of minutes the generator should be on,
the amount of fuel needed is divided by the flow
rate and multiplied by 60. In our case, .21 (amount
of fuel needed) divided by .55 (flow rate)
multiplied by 60 equals 22.9 minutes.
The CO2 required for at least one grow room was
supplied using gas lamps. The grower said that
she thought it was a shame that the fuel was used
only for the CO2 and thought her plants would
benefit from the additional light. She originally
had white gas lamps spaced evenly throughout the
garden. She replaced them after the first crop
with gas lamps all hooked up to a central LP gas
tank. She only had to turn the unit on and light
the lamps each day. It shut itself off. She
claims the system worked very well. CO2 should be
replenished every 3 hours during the light cycle,
since it is used up by the plants and leaks from
the room into the general atmosphere. Well-ventilated
rooms should be replenished more often. It is
probably more effective to have a generator or
tank releasing CO2 for longer periods at slower
rates than for shorter periods of time at higher
rates.
Marijuana Grower's Handbook - part 13 of 33
"Temperature"
Marijuana plants are very hardy and survive
over a wide range of temperatures. They can
withstand extremely hot weather, up to 120
degrees, as long as they have adequate supplies
of water. Cannabis seedlings regularly survive
light frost at the beginning of the season. Both
high and low temperatures slow marijuana's rate
of metabolism and growth. The plants function
best in moderate temperatures - between 60 and 85
degrees. As more light is available, the ideal
temperature for normal plant growth increases. If
plants are given high temperatures and only
moderate light, the stems elongate. Conversely,
strong light and low temperatures decrease stem
elongation. During periods of low light, strong
elongation is decreased by lowering the
temperature. Night temperatures should be 10-15
degrees lower than daytime temperatures.
Temperatures below 50 degrees slow growth of most
varieties. When the temperature goes below 40
degrees, the plants may experience some damage
and require about 24 hours to resume growth. Low
nighttime temperatures may delay or prevent bud
maturation. Some equatorial varieties stop growth
after a few 40 degree nights.
A sunny room or one illuminated by high wattage
lamps heats up rapdily. During the winter the
heat produced may keep the room comfortable.
However the room may get too warm during the
summer. Heat rises, so that the temperature is
best measured at the plants' height. A room with
a 10 foot ceiling may feel uncomfortably warm at
head level but be fine for plants 2 feet tall.
If the room has a vent or window, an exhaust fan
can be used to cool it. Totally enclosed spaces
can be cooled using a water conditioner which
cools the air by evaporating water. If the room
is lit entirely by lamps, the day/night cycle can
be reversed so that the heat is generated at
night, when it is cooler out.
Marijuana is a low-temperature tolerant. Outdoors,
seedlings sometimes pierce snow cover, and older
plants can withstand short, light frosts.
Statistically, more males develop in cold
temperatures. However, low temperatures slow down
the rate of plant metabolism. Cold floors lower
the temperature in containers and medium, slowing
germination and growth. Ideally, the medium
temperature should be 70 degrees. There are
several ways to warm the medium. The floor can be
insulated using a thin sheet of styrofoam, foam
rubber, wood or newspaper. The best way to
insulate a container from a cold floor is to
raise the container so that there is an air space
between it and the floor.
Overhead fans, which circulate the warm air
downward from the top of the room also warm the
medium.
When the plants' roots are kept warm, the rest of
the plant can be kept cooler with no damage. Heat
cables or heat mats, which use small amounts of
electricity, can be used to heat the root area.
These are available at nursery supply houses.
When watering, tepid water should be used.
Cultivators using systems that recirculate water
can heat the water with a fish tank heater and
thermostat. If the air is cool, 45-60 degrees,
the water can be heated to 90 degres. If the air
is warm, over 60 degrees, 70 degrees for the
water is sufficient. The pipes and medium absorb
the water down a bit before it reaches the roots.
Gardens using artificial lighting can generate
high air temperatures. Each 100 watt metal halide
and ballast emits just a little less energy can a
10 amp heater. Several lights can raise the
temperature to an intolerable level. In this case
a heat exchanger is required. A venting fan or
misters can be used to lower temperatures.
Misters are not recommended for use around lights.
Greenhouses can also get very hot during the
summer. If the sun is very bright, opaquing paint
may lower the amount of light and heat entering
the greenhouse. Fans and cooling mats also help.
Cooling mats are fibrous plastic mats which hold
moisture. Fans blow air through the mats which
lowers the greenhouse temperature. They are most
effective in hot dry areas. They are available
througn nursery supply houses.
Marijuana Grower's Handbook - part 15 of 33
"pH and Water"
The pH is the measure of acid-alkalinity
balance of a solution. It is measured on a scale
of 0-14, with 0 being the most acid, 7 being
neutral, and 14 being most alkaline. [pH:In case
you're wondering, I'm a total 0!] Most nutrients
the plants use are soluble only in a limited
range of acidity, between about 6 to about 7.5,
neutral. Should the water become too acidic or
alkaline, the nutrients dissolved in the water
become too acidic or alkaline, the nutrients
dissolved in the water precipitate and become
unavailable to the plants. When the nutrients are
locked up, plant growth is slowed. Typically, a
plant growing in an environment with a low pH
will be very small, often growing only a few
inches in several months. Plants growing in a
high pH environment will look pale and sickly and
also have stunted growth. All water has a pH
which can be measured using aquarium or garden pH
chemical reagent test kits or a pH meter. All of
these items are available at local stores and are
easy to use. Water is pH-adjusted after nutrients
are added, since nutrients affect the pH. Once
the water is tested it should be adjusted if it
does not fall within the pH range of 6 to 7.
Ideally the range should be about 6.2-6.8.
Hydroponic supply companies sell measured
adjusters which are very convenient and highly
recommended. The water-nutrient solution can be
adjusted using common household chemicals. Water
which is too acidic can be neutralized using
bicarbonate of soda, wood ash, or by using a
solution of lime in the medium.
Water which is too alkaline can be adjusted using
nitric acid, sulfuric acid, citric acid (Vitamin
C) or vinegar. The water is adjusted using small
increments of chemicals. Once a standard measure
of how much chemical is needed to adjust the
water, the process becomes fast and easy to do.
Plants affect the pH of the water solution as
they remove various nutrients which they use.
Microbes growing in the medium also change the pH.
For this reason growers check and adjust the pH
periodically, about once every two weeks.
The pH of water out of the tap may change with
the season so it is a good idea to test it
periodically.
Some gardeners let tap water sit for a day so
that the chlorine evaporates. They believe that
chlorine is harmful to plants. The pH of the
planting medium affects the pH of the liquid in
solution. Medium should be adjusted so that it
tests between 6.2-6.8. This is done before the
containers are filled so that the medium could be
adjusted in bulk. Approximately 1-2 lbs. of
dolomitic limestone raises the pH of 100 gallons
(4.5-9 grams per gallon) of soil 1 point. Gypsum
can be used to lower the pH of soil or medium.
Both limestone and gypmsum have limited
solubility.
There are many forms of limestone which have
various effectiveness depending on their
chemistry. Each has a rating on the package.
Marijuana Grower's Handbook - part 14 of 33
"Air and Humidity"
Besides temperatures and CO2 content, air has other qualities including dust content, electrical charge and humidity.
Dust
"Dust" is actually composed of many different-sized solid and liquid particles which float in the gaseous soup. The particles include organic fibers, hair, other animal and vegetable particles, bacteria, viruses, smoke and odoriferous liquid particles such as essential oils, and water-soluble condensates. Virtually all of the particles have a positive electrical charge, which means that they are missing an electron, and they float (due to electrical charge) through various passing gases. The dust content of the air affects the efficiency of the plant's ability to photosynthesize. Although floating dust may block a small amount of light, dust which has precipitated on leaves may block large amounts. Furthermore, the dust clogs the pores through which plants transpire. Dust can easily be washedoff leaves using a fine mist spray. Water must be prevented from touching and shattering the hot glass of the lights.
Negative Ions
in unindustrialized verdant areas and near
large bodies of water, the air is negatively
charged, that is, there are electrons floating in
the air unattached to atoms or molecules. In
industrialized areas or very dry regions, the air
is positively charged; there are atoms and
molecules missing electrons.
Some researchers claim that the air's electrical
charge affects plant growth (and also animal
behavior). They claim that plants in a positively
charged environment grow slower than those in a
negatively charged area. Regardless of the
controversy regarding growth and the air's
electrical charge, the presence of negative ions
creates some readily observable effects. Odors
are characteristic of positively charged
particles floating in the air. A surplus of
negative ions causes the particles to precipitate
so that there are no odors. With enough negative
ions, a room filled with pungent, flowering
sinsemilla is odorless. Spaces with a "surplus"
negative ion charge have clean, fresh smelling
air. Falling water, which generates negative ions,
characteristically creates refreshing air. Dust
particles are precipitated so that there are
fewer bacteria and fungus spores floating in the
air, as well as much less dust in general. This
lowers the chance of infection. Many firms
manufacture "Negative Ion Generators",
"Ionizers", and "Ion Fountains",
which disperse large quantities of negative ions
into the atmosphere. These units are inexpensive,
safe and recommended for all growing areas. Ion
generators precipitate particles floating in the
air. With most generators, the precipitating
particles land within a radius of two feet of the
point of dispersal, collecting quickly and
developing into a thick film of grime. Newspaper
is placed around the unit so that the space does
not get soiled. Some newer units have a
precipitator which collects dust on a charged
plate instead of the other surrounding surfaces.
This plate can be rougly simulated by grounding a
sheet a aluminum foil. To ground foil, either
attach it directly to a metal plumbing line or
grounding box; for convenience, the foil can be
held with an alligator clip attacked to the
electrical wire, which is attached to the
grounding source. As the foil gets soiled, it is
replaced.
Humidity
Cannabis grows best in a mildly humid environment: a relative humidy of 40-60 percent. Plants growing in drier areas may experience chronic wilt and necrosis of the leaf tips. Plants growing in a wetter environment usually experience fewer problms; however, the buds are more susceptible to molds which can attack a garden overnight and ruin a crop. Growers are rarely faced with too dry a growing area. Since the space is enclosed, water which is evaporated or transpired by the plants increases the humidity considerably. If there is no ventilation, a large space may reach saturation level within a few days. Smaller spaces usually do not have this buildup because there is usually enough air movement to dissipate the humdity. The solution may be as easy as opening a window. A small ventilation fan can move quite a bit of air out of a space and may be a convenient way of solving the problem. Humidity may be removed using a dehumidifier in gardens without access to convenient ventilation. Dehumidifiers work the same way a refrigerator does except that instead of cooling a space, a series of tubes is cooled causing atmospheric water to condense. The smallest dehumidifiers (which can dry out a large space) use about 15 amps. Usually the dehumidifier needs to run only a few hours a day. If the plant regimen includes a dark cycle, then the dehumidifier can be run when the lights are off, to ease the electrical load.
Air Circulation
A close inspection of a marijuana leaf reveals many tiny hairs and a rough surface. Combined, these trap air and create a micro-environment around the plant. The trapped air contains more humidity and oxygen and is warmer, which differs significantly in the composition and temperature from the surrounding atmosphere. The plant uses CO2 so there is less left in the air surrounding the leaf. Marijuana depends on air currents to move this air and renew the micro-environment. If the air is not moved vigorously, the growth rate slows, since the micro-environment becomes CO2 depleted. Plants develop firm, sturdy stems as the result of environmental stresses. Outdoors, the plants sway with the wind, causing tiny breaks in the stem. These are quickly repaired bythe plant's reinforcing the original area and leaving it stronger than it was originally. Indoors, plants don't usually need to cope with these stresses so their stems grow weak unless the plants receive a breeze or are shaken by the stems daily. A steady air flow form the outdoor ventilation may be enough to keep the air moving. If this is not available, a revolving fan placed several feet from the nearest plant or a slow-moving overhead fan can solve the problem. Screen all air intake fans to prevent pests.
Marijuana Grower's Handbook - part 16 of 33
"Nutrients"
Marijuana requires a total of 14 nutrients
which it obtains through its roots. Nitrogen (N),
Phosophorous (P), and Potassium (K) are called
the macro-nutrients because they are used in
large quantities by the plant. The percentages of
N, P, and K are always listed in the same order
on fertilizer packages.
Calcium (Ca), sulfur (S), and magnesium (Mg) are
also required by the plants in fairly large
quantities. These are often called the secondary
nutrients.
Smaller amounts of iron (Fe), zinc (Zn),
manganese (Mn), boron (B), cobalt (Co), copper (Cu),
molybdenum (Mo) and chlorine (Cl) are also needed.
These are called micro-nutrients.
[pH:And you thought chemistry wasn't good for
anything!] Marijuana requires more N before
flowering than later in its cycle. When it begins
to flowe, marijuana's use of P increases.
Potassium requirements increase after plants are
fertilized as a result of seed production. Plants
which are being grown in soil mixes or mixes with
nutrients added such as compost, manure or time-releasing
fertilizers may need no additional fertilizing or
only supplemental amounts of the plants begin to
show deficiencies.
The two easiest and most reliable ways to meet
the plant's needs are to use a prepared
hydroponic fertilizer or an organic water-soluble
fertilizer. Hydroponic fertilizers are blended as
complete balanced formulas. Most non-hydroponic
fertilizers usually contain only the
macronutrients (N, P, and K). Organic fertilizers
such as fish emulsion and other blends contain
trace elements which are found in the organic
matter from which they are derived.
Most indoor plant fertilizers are water-soluble.
A few of them are time-release formulas which are
mixed into the medium as it is being prepared.
Plants grown in soil mixes can usually get along
using regular fertilizers but plants grown in
prepared soilless mixes definitely require
micronutrients.
As the seeds germinate they are given a nutrient
solution high in N such as a 20-10-10 or 17-10-12.
These are just two possible formulas; any with a
high proportion of N will do.
Formulas which are not especially high in N can
be used and supplemented with a high N ferilizer
such as fish emulsion (which may create an odor)
or the Sudbury X component fertilizer which is
listed 44-0-0. Urine is also very high in N and
is easily absorbed by the plants. It should be
diluted to one cup urine per gallon of water.
The plants should be kept on a high N fertilizer
regimen until they are put into the flowering
regimen.
During the flowering cycle, the plants do best
with a formula lower in N and higher in P, which
promotes bloom. A fertilizer such as 5-20-10 or
10-19-12 will do. (Once again, these are typical
formulas, similar ones will do).
Growers who make their own nutrient mixes based
on parts per million of nutrient generally use
the following formulas.
Chart 15-1: Nutrient/Water Solution In Parts Per Million (PPM)
+-----------------------------------+---------+---------+---------+
| | N | P | K |
+-----------------------------------+---------+---------+---------+
| Germination - 15 to 20 days | 110-150 | 70-100 | 50-75 |
+-----------------------------------+---------+---------+---------+
| Fast Growth | 200-250 | 60-80 | 150-200 |
+-----------------------------------+---------+---------+---------+
| Pre-Flowering | 70-100 | 100-150 | 75-100 |
| 2 weeks before turning light down | | | |
+-----------------------------------+---------+---------+---------+
| Flowering | 0-50 | 100-150 | 50-75 |
+-----------------------------------+---------+---------+---------+
| Seeding - fertilized flowers | 100-200 | 70-100 | 100-150 |
+-----------------------------------+---------+---------+---------+
Plants can be grown using a nutrient solution
containing no N for the last 10 days. Many of the
larger leaves yellow and wither as the N migrates
from the old to the new growth. The buds are less
green and have less of a minty (chlorophyll)
taste.
Many cultivators use several brands and formulas
of fertilizer. They either mix them together in
solution or switch brands each feeding. Plant N
requirements vary by weather as well as growth
cycle. Plants growing under hot conditions are
given 10-20% less N or else they tend to elongate
and to grow thinner, weaker stalks. Plants in a
cool or cold regimen may be given 10-20% more N.
More N is given under high light conditions, less
is used under low light conditions. Organic
growers can make "teas" from organic
nutrients by soaking them in water. Organic
nutrients usually contain micronutrients as well
as the primary ones. Manures and blood meal are
among the most popular organic teas, but other
organic sources of nutrients include urine, which
may be the best source for N, as well as blood
meal and tankage. Organic fertilizers vary in
their formulas. The exact formula is usually
listed on the label. Here is a list of common
organic fertilizers which can be used to make
teas:
Chart 15-2: Organic Fertilizers +----------------+-----+------+------+---------------------------------+
| Cow manure | 1.5 | .85 | 1.75 | The classic tea. Well- | | (dried) | | | | balanced formula. Medium | | | | | | availability. | +----------------+-----+------+------+---------------------------------+ | Dried blood | 13 | 3 | 0 | Nutrients dissolve easier | | | | | | than bloodmeal | +----------------+-----+------+------+---------------------------------+ | Chicken manure | 3.5 | 1.5 | .85 | Excellent nutrients | +----------------+-----+------+------+---------------------------------+ | Wood ashes | 0 | 1.5 | 7 | Water-soluble. Very alkaline | | | | | | except with acid wood such | | | | | | as walnut | +----------------+-----+------+------+---------------------------------+ | Granite dust | 0 | 0 | 5 | Dissolves slowly | +----------------+-----+------+------+---------------------------------+ | Rock phosphate | 0 | 35 | 0 | Dissolves gradually | | (phosphorous) | | | | | +----------------+-----+------+------+---------------------------------+ | Urine (human, | .5 | .003 | .003 | N immediately available | | fresh) | | | | |
+----------------+-----+------+------+---------------------------------+
Commercial water-soluble fertilizers are
available. Fish emulsion fertilizer comes in 5-1-1
and 5-2-2 formulas and has been used by satisfied
growers for years.
A grower cannot go wrong changing hydroponic
water/nutrient solutions at least once a month.
Once every two weeks is even better. The old
solution could be measured, reformulated,
supplemented and re-used; unless large amounts of
fertilizer are used, such as in a large
commercial greenhouse, it is not worth the effort.
The old solution may have many nutrients left,
but it may be unbalanced since the plants have
drawn specific chemicals. The water can be used
to water houseplants or an outdoor garden, or to
enrich a compost pile.
Experienced growers fertilize by eyeing the
plants and trying to determine their needs when
minor symptoms of deficiencies become apparent.
If the nutrient added cures the deficiency, the
plant usually responds in apparent ways within
one or two days. First the spread of the symptom
stops. With some minerals, plant parts that were
not too badly damaged begin to repair themselves.
Plant parts which were slightly discolored may
return to normal. Plant parts which were severely
damaged or suffered from necrosis do not recover.
The most dramatic changes usually appear in new
growth. These parts grow normally. A grower can
tell just by plant parts which part grew before
deficiencies were corrected. [pH:What's in yer
nuggets? Parts. Plant parts. Processed plant
parts. HAHAHAHAHAHAHA] Fertilizers should be
applied on the low side of recommended rates.
Overdoses quickly (within hours) result in
wilting and then death. The symptoms are a sudden
wilt with leaves curled under. To save plants
suffering from toxic overdoses of nutrients,
plain water is run through systems to wash out
the medium.
Gardens with drainage can be cared for using a
method commercial nurseries employ. The plants
are watered each time with a dilute nutrient/water
solution, usually 20-25% of full strength. Excess
water runs off. While this method uses more water
and nutrients than other techniques, it is easy
to set up and maintain.
When nutrient deficiencies occur, especially
multiple or micronutrient deficiencies, there is
a good chance that the minerals are locked up (precipitated)
because of pH. [pH:That's not very fair, I wasn't
even there!] Rather than just adding more
nutrients, the pH must be checked first. If
needed, the pH must be changed by adjusting the
water. If the pH is too high, the water is made a
lower pH than it would ordinarily be; if too low
the water is made a higher pH. To get nutrients
to the plant parts immediately, a dilute foliar
spray is used. If the plant does not respond to
the foliar spray, it is being treated with the
wrong nutrient.
NUTRIENTS
Nitrogen (N)
Marijuana uses more N than any other nutrient.
It is used in the manufacture of chlorophyll. N
migrates from old growth to new, so that a
shortage is likely to cause first pale green
leaves and then the yellowing and withering of
the lowers leaves as the nitrogen travels to new
buds. Other deficiency symptoms include smaller
leaves, slow growth and a sparse rather than
bushy profile.
N-deficient plants respond quickly to
fertilization. Within a day or two, pale leaves
become greener and the rate and size of new
growth increases. Good water-soluble sources of
nitrogen include most indoor and hydroponic
fertizliers, fish emulsion, and urine, along with
teas made from manures, dried blood or bloodmeal.
There are many organic additives which release N
over a period of time that can be added to the
medium at the time of planting. These include
manures, blood, cottonseed meal, hair, fur, or
tankage.
Phosphorous (P)
P is used by plants in the transfer of light
energy to chemical compounds. It is also used in
large quantities for root growth and flowering.
Marijuana uses P mostly during early growth and
flowering. Fertilizers and nutrient mixes usually
supply adequate amounts of P during growth stages
so plants usually do not experience a deficiency.
Rock phosphate and bone meal are the organic
fertilizers usually recommended for P deficiency.
However they release the mineral slowly, and are
more suited to outdoor gardening than indoors.
They can be added to medium to supplement soluble
fertilizers.
P-devicient plants have small dark green leaves,
with red stems and red veins. The tips of lower
leaves sometimes die. Eventually the entire lower
leaves yellow and die. Fertilization affects only
new growth. Marijuana uses large quantities of P
during flowering. Many fertilizer manufacturers
sell mixes high in P specifically for blooming
plants.
Potassium (K)
K is used by plants to regulate carbohydrate metabolism, chlorophyll synthesis, and protein synthesis as well as to provide resistance to disease. Adequate amounts of K result in strong, sturdy stems while slightly deficient plants often grow taller, thinner stems. Plants producing seed use large amounts of K. Breeding plants can be given K supplements to assure well-developed seed. Symptoms of greater deficiencies are more apparent on the sun leaves (the large lower leaves). Necrotic patches are found on the leaf tips and then in patches throughout the leaf. The leaves also look pale green. Stems and flowers on some plants turn deep red or purple as a result of K deficiencies. However, red stems are a genetic characteristic of some plants so this symptom is not foolproof. Outdoors, a cold spell can precipitate K and make it unavailable to the plants, so that almost overnight the flowers and stems turn purple. K deficiency can be treated with any high-K fertilizer. Old growth does not absorb the nutrient and will not be affected. However, the new growth will show no signs of deficiency within 2 weeks. For faster results the fetilizer can be used as a foliar spray. K deficiency does not seem to be a crucial problem. Except for the few symptoms, plants do not seem to be affected by it.
Calcium (Ca)
Ca is used during cell splitting, and to build the cell membranes. Marijuana also stores "excess" Ca for reasons unknown. I have never seen a case of Ca deficiency in cannabis. Soils and fertilizers usually contain adequate amounts. It should be added to planting mixes when they are being formulated at the rate of 1 tablespoon per gallon or 1/2 cup per cubic foot of medium.
Sulfur (S)
S is used by the plant to help regulate
metabolism, and as a constituent of some vitamins,
amino acids and proteins. It is plentiful in soil
and hydroponic mixes.
S deficiencies are rare. First, new growth
yellows and the entire plant pales.
s deficiencies are easily solved using Epsom
salts at the rate of 1 tablespoon per gallon of
water.
Magnesium (Mg)
Mg is the central atom in chlorophyll and is
also used in production of carbohydrates. (Chlorophyll
looks just like hemoglobin in blood, but has a Mg
atom. Hemoglobin has an Fe atom). In potted
plants, Mg deficiency is fairly common, since
many otherwise well-balanced fertilizers do not
contain it.
Deficiency symptoms start on the lower leaves
which turn yellow, leaving only the veins green.
The leaves curl up and die along the tips and
edges. Growing shoots are pale green and, as the
condition continues, turn almost white.
Mg deficiency is easily treated using Epsom salts
(MgSO4) at the rate of 1 tablespoon per gallon of
water. For faster results, a foliar spray is used.
Once Mg deficiency occurs, Epsom salts should be
added to the solution each time it is changed.
Dolomitic limestone contains large amounts of Mg.
Iron (Fe)
Fe deficiency is not uncommon. The growing shoots are pale or white, leaving only dark green veins. The symptoms appear similar to Mg deficiencies but Fe deficiencies do not affect the lower leaves. Fe deficiencies are often the result of acid-alkalinity imbalances. Fe deficiencies sometimes occur together with zinc (Zn) and manganese (Mn) deficiencies so that several symptoms appear simultaneously. Deficiencies can be corrected by adjusting the pH, adding rusty water to the medium, or using a commercial supplement. Fe supplements are sold alone or in a mix combined with Zn and Mn. To prevent deficiencies, some growers add a few rusting nails to each container. One grower using a reservoir system added a pound of nails to the holding tank. The nails added Fe to the nutrient solution as they rusted. Dilute foliar sprays can be used to treat deficiencies.
Manganese (Mn)
Symptoms of Mn deficiency include yellowing and dying of tissue between veins, first appearing on new growth and then throughout the plant. Deficiencies are solved using an Fe-Zn-Mn supplement.
Zinc (Zn)
Zn deficiency is noted first as yellowing and necrosis of older leaf margins and tips and then as twisted, curled new growth. Treatment with a Fe-Zn-Mn supplement quickly relieves symptoms. A foliar spray speeds the nutrients to the leaf tissue.
Boron (B)
B deficiency is uncommon and does not usually occur indoors. Symptoms of B deficiency start at the growing tips, which turn grey or brown and then die. This spreads to the lateral shoots. A B deficiency (pH:A, B, deficient C!) is treated by using 1/2 teaspoon boric acid, available in pharmacies, added to a gallon of water. One treatment is usually sufficient.
Molybdenum (Mo)
Mo is used by plants in the conversion of N to
forms that the plant can use. It is also a
consituent of some enzymes. Deficiency is unusual
indoors.
Symptoms start with paleness, then yellowing of
middle leaves which progress to the new shoots
and growing tips, which grow twisted. The early
symptoms almost mimic N deficiency. Treatment
with N may temporarily relieve the symptoms but
they return within a few weeks. Mo is included in
hydroponic fertilizers and in some trace element
mixes. It can be used as a foliar spray.
Copper (Cu)
Cu is used by plants in the transfer of
electrical charges which are manipulated by the
plant to absorb nutrients and water. It is also
used in the regulation of water content and is a
constituent of some enzymes. Cu deficiencies are
rare and mimic symptoms of overfertilization. The
leaves are limp and turn under at the edges. Tips
and edges of the leaves may die and whole plant
looks wilted.
A fungicide, copper sulfate, (CuSO$) can be used
as a foliar spray to relieve the deficiency.
NUTRIENT ADDITIVES
Various additives are often suggested to boost
the nutrient value of the water/nutrient solution.
Here are some of them: WETTING AGENTS. Water
holds together through surface tension,
preventing it from dispersing easily over dry
surfaces. Wetting agents decrease the surface
tension and allow the water to easily penetrate
evenly throughout the medium preventing dry spots.
Wetting agents are helpful when they are used
with fresh medium and as an occasional additive.
Wetting agents should not be used on a regular
basis. They may interfere with plants' ability to
grow root hairs, which are ordinarily found on
the roots. They are available at most plant
nurseries.
SEAWEED. Washed, ground seaweed contains many
trace elements and minerals used by plants. It
may also contain some hormones or organic
nutrients not yet identified.
KELP. Kelp seems to be similar to seaweed in
nutrient value. Proponents claim that it has
other, as yet undefined organic chemicals that
boost plant growth.
SEA WATER. Salt water contains many trace
elements and organic compounds. Some hydroponists
claim that adding 5-10% sea water to the nutrient
solution prevents trace element problems. It may
be risky.
DEFICIENCIES OF NUTRIENT ELEMENTS IN MARIJUANA
Suspected Element +----------------------+---+---+---+----+----+----+----+---+----+---+------+
| Symptoms | N | P | K | Mg | Fe | Cu | Zn | B | Mo | Mn| Over | | | | | | | | | | | | |Fertil| +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Yellowing of: | | | | | | | | | | | | | | | | | | | | | | | | | | Younger leaves | | | | | X | | | | | X | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Middle leaves | | | | | | | | | X | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Older leaves | X | | X | X | | | X | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Between veins | | | | X | | | | | | X | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Old leaves drop | X | | | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Leaf Curl Over | | | | X | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Leaf Curl Under | | | X | | | X | | | | | X | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Leaf tips burn | | | | | | | | | | | | | | | | | | | | | | | | | | Younger leaves | | | | | | | | X | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Older leaves | X | | | | | | X | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Young leaves wrinkle | | | | | | | | | | | | | and curl | | | X | | | | X | X | X | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Necrosis | | | X | X | X | | X | | | X | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Leaf growth stunted | X | X | | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Dark green/purplish | | | | | | | | | | | | | leaves and stems | | X | | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Pale green leaf color| X | | | | | | | | X | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Mottling | | | | | | | X | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Spindly | X | | | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Soft stems | X | | X | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Hard/brittle stems | | X | X | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Growing tips die | | | X | | | | | X | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Stunted root growth | | X | | | | | | | | | | +----------------------+---+---+---+----+----+----+----+---+----+---+------+ | Wilting | | | | | | X | | | | | |
+----------------------+---+---+---+----+----+----+----+---+----+---+------+
Marijuana Grower's Handbook - part 17 of 33
"Novel Gardens"
Many people who would like to grow their own
think that they don't have the space. There are
novel techniques that people can use to grow
grass anywhere. Even people with only a closet,
crawl space or just a shelf can grow their own.
The smallest space that can be used is a shelf 15-24
inches high. First, the space should be prepared
as any other garden by making it reflective,
using flat white paint, the dull side of aluminum
foil, or white plastic. Fluorescents are the
easiest and best way to illuminate the space.
About twenty watts per square foot are used, or
two tubes per foot of width. VHO fluorescents can
be used to deliver more light to the system.
Plants can be started in 6 ounce cups or 8 to 16
ounce milk cartons placed in trays for easier
handling.
With a shelf of 3 feet or higher, plants can be
grown in larger containers such as 4 to 6 inch
pots, half gallon milk containers trimmed to hold
only a quart.
The plants can be grown vertically only, as they
normally grow, or moved to a horizontal position
so that the main stem runs parallel to the light
tubes. The plants' new growth will immediately
face upwards towards the light. One gardener used
an attic space only 4 feet tall. She let the
plants grow until they reached 3 feet and then
turned them on their side. They used more floor
space so she opened up a second bank of lights.
At maturity, the plants were 3.5 feet long and 2.5
feet tall. Another grower turned his basement
with an 8 foot ceiling into a duplex growing
chamber. Each unit had 3 foot tall plants. If the
plants are to be turned horizontally, then they
are best grown in plastic bags or styrofoam cups
so that they can be watered easily in their new
positions. After being turned on the side, a hole
is cut in the new top so the plants can be
watered easily.
Some growers have wall space without much depth.
This space can be converted to a growing area
very easily. The space is painted white and a
curtain is made so that the space is seperated
from the surrounding environment; this will keep
light in and offers protection from nosey guests.
The fluorescents should be placed so that they
form a bank facing the plants. Although the
plants naturally spread out, their depth or width
can be controlled by training them using stakes
or chicken wire placed on a frame. Wire or
plastic netting is attached to the walls so that
there is at least a 1 inch space between the wire
and the wall. Some people build a frame out of 2x4's.
Twist ties are used to hold the branches to the
frame. Additional light can be supplied by
placing a fluorescent unit on either end of the
garden or along its length.
Growers who have a little more space for their
garden, with a minimum width of 1 or 2 feet, can
grow plants without training them. Fluorescent
lights can be used to light the garden by hanging
the light fixture from the top. All sides should
be covered with reflective material. A metal
halide lamp mounted on a movable apparatus will
help the plants grow even faster so that the
entire garden is illuminated several times during
each light cycle. Some people can spare only a
small closet. Closets usually are designed in one
of two shapes: square or long and rectangular. In
any closet up to six feet long the simplest way
to grow is by painting the inside of the closet
white and hanging a metal halide light from the
ceiling. Closets with dimensions of 5x5 or less
need only a 400 watt metal halide although they
can accomodate 1000 watt lamps. Larger areas need
at least two 400 watt halide lamps.
Thin, rectangular closets are served best by a
metal halide unit mounted on a solar shuttle type
device. A fluorescent light unit hung from above
the garden also works well. Additional
fluorescent tubes can be used to supplement the
top lights. It is convenient to mount them on
either end of the hanging fixture if the closet
is long enough so that they do not use potential
growing space. A closet 2 feet by 7 feet might be
illuminated by a 400 watt metal halide on a track,
two 6 foot long VHOs or 4 regular fluorescent
tubes hung from the ceiling. A grower might also
use 14 screw-in 8 inch circular reflectors
mounted on two 2x4s and hung above the garden.
About 8 combination 8 and 12 inch circular
fixtures will also light the area.
As the plants grow taller, fluorescent lit
gardens will respond to fluorescent tubes placed
on the sides of the garden below the tops of the
plants. This light wll help lower buds develop.
One of the main problems inherent in the nature
of small gardens is the lack of ventilation and
CO2. For good growth rates the air should be
enriched with CO2 or provided with a fan for
ventilation.
Marijuana Grower's Handbook - part 18 of 33
"Containers"
To save space, plants can be germinated in
small containers and transplanted to
progressively larger ones. Seeds can be
germinated in 2 x 1 inch trays or in peat pellets
and remain in these containers for about one week.
Four inch diameter containers can hold the plants
for 2 to 3 weeks without inhibiting growth.
Styrofoam cups weighted at the bottom with sand
or gravel so they don't tip over are convenient
germinating containers. If plants are to be
germinated at one location and then moved to
another location, styrofoam and other lightweight
plastic cups are ideal containers. Six ounce cups
hold plants for about 7-10 days after germination.
Sixteen ounce cups hold plants 10-20 days, as
long as the plants receive frequent water
replenishments.
Half gallon containers can support plants for 25-40
days. Plants probably grow a bit faster without
being transplanted. However, the saving in space
for a multi-crop system or even a multi-light
system more than compensates for the loss in
growth rate. Figure that each transplanting costs
the plants 3-4 days of growth. Growers using a 2
light system need to use only one lamp for the
first 4-6 weeks the plants are growing. Multi-crop
gardens need to use only a fraction of the space
for the first 3 to 8 weeks after germination.
Some growers sex the plants before either the
first or second transplanting. They find it
easier to control the light-darkness cycle in a
small space. Another crop's flowering cycle may
coincide with the seedlings. To sex the small
plants, only a small area is required in the grow
room.
A good rule of thumb is that for each two feet of
growth, a half gallon of growing medium is
required in a garden in which fertilizers are
supplied throughout the growing period. A 2 foot
plant requires a 1/2 gallon container, a 5 foot
plant uses a 2.5 gallon container and a 10 foot
plant requires a 5 gallon unit. Of course, plants'
width or depth varies too, so these are
approximations. Certainly there is no harm done
in growing a plant in a container larger than is
required. However, growing plants in containers
which are too small delays growth or may even
stunt the plants. Plants growing in soil or
compost-based mediums do better in slightly
larger containers. A rule of thumb for them is a
3/4 gallon medium for each foot of growth. A 5
foot plant requires a 3 and 3/4 gallon container.
One grower wrote "I never use more than 4
gallon containers and have grown plants to 12
feet high with no signs of deficiencies. I was
able to water at 2-3 day intervals. My 3 month
old plants under light were in 1/2 gallon
containers with and without wicks." This
grower always uses small (1/2 gallon) containers
for his spring greenhouse crop. A plant growing
in an organic-based medium such as soil-compost-manure
and additives needs no fertilization if it is
given a large enough container. For a five month
growing season, plants in a rich mixture require
1 to 1.5 gallons medium per foot. A 5 foot plant
requires a container holding 5-7.5 gallons.
Containers should have a slight graduation so
that plants and medium can slide out easily.
Plastic containers or pots are the most
convenient to use. They are lightweight, do not
break and are inert. Metal containers react with
the nutrients in the solution. Plastic bags are
convenient containers. Grow bags have a square
bottom so that they balance easily. However
growers use all kinds of plastic bags for
cultivation. Fiber containers are also popular.
They are inexpensive, last several growing
seasons and are easy to dispose of.
Marijuana Grower's Handbook - part 19 of 33
"When to Plant"
Marijuana growers using only artificial light
can start at any time since the grower determines
the plant's environment and stimulates seasonal
variations by adjusting the light/darkness
periods. Gardeners using natural light either as
a primary or secondary source must take the
seasons into account. They plant in the spring -
from April through June. These plants will be
harvested between September and November and no
artificial light may be needed as long as there
is plenty of direct sunshine. Supplemental
artificial light may help the plants to maturity
in the fall, when the sun's intensity declines
and there are overcast days. The angle of the sun's
path changes over the season too. Areas may
receive indirect sun during part of the growing
season. In overcast areas, and even sunny places
receiving direct sunlight, 4-6 hours of
supplemental metal halide light during the
brightest part of the day is all that is needed
during September/October to help the buds mature.
One lamp will cover about 100 square feet or an
area 10 by 10 feet. Growers using natural light
are not restricted to one season. It is feasible
to grow 3 or 4 crops a year using supplemental
light. In early October, before the plants are
harvested, seeds are started in a seperate area.
Since little room is needed for the first few
weeks, they can be germinated on a shelf. In
addition to natural light, the plants should get
a minimum of 6 hours of artificial light per day
at the rate of about 10 watts per square foot.
For fastest growth, the plants should receive 24
hours of light a day. Seedlings may receive light
only during normal day light hours except that
they require an interruption of the night cycle
so they do not go into the flowering stage
prematurely. If metal halide lamps are being used,
a seperate light system should be installed with
incandescent or fluorescent lights on a timer so
that the seedlings do not have a long period of
uninterrupted darkness. One 60 watt incandescent
bulb or one 22 watt fluorescent tube is used per
square yard (3 by 3 feet). The bulbs can be
flashed on for a few minutes using a multi-cycle
timer during the middle of the dark period.
Gardeners with large spaces sometimes stagger the
timing of the night lights.
Incandescent bulbs are not very effecient, but
they provide enough light to prevent flowering,
they are easy and inexpensive to set up and
maintain, and they light up almost immediately.
In addition, they emit a high percentage of red
light, which is part of the spectrum used by
plants to regulate photoperiod responses.. Metal
halides require about 10 minutes to attain full
brightness. Metal halide ballasts wear out faster
when they are turned on and off a lot, so it is
cheaper to flash incandescents. In late December,
the incandescents are turned off so that they no
longer interrupt the night cycle. Within a week
or two the plants will begin to flower. They will
be ready to harvest in 6 or 8 weeks. At the same
time that the incandescents are turned off the
winter crop, seeds are started for the spring
crop. They are kept on the interrupted night
regimen until late winter, around March 1-10. The
plants will begin to flower and be ready in late
May and early June. The spring crop should be
planted with short season plants so that they do
not revert back to vegetative growth as the days
get longer. Long season varieties are more likely
to revert.
After the flowers are formed, the spring crop
plants will revert back to vegetative growth. New
leaves will appear and the plant will show
renewed vigor. The plant can be harvested again
in the fall, or new seds can be germinated for
the fall crop.
One grower reported that he makes full use of his
greenhouse. He starts his plants indoors in late
November and starts the flowering cycle in the
beginning of Februaru. The plants are ripe by the
end of April, then he lets the plants go back
into vegetative growth for a month and a half.
Then he starts to shade them again and harvests
in late August. Next he puts out new, month-old,
foot-high plants. He lets them grow under natural
light, but breaks the darkness cycle using
incandescent lights. In mid-September he shuts
the lights off, and the plants mature in early
November.
Marijuana Grower's Handbook - part 20 of 33
"Planting"
Growers usually figure that 1/4 - 1/3 of the
seeds they plant reach maturity. Usually 40-50%
of the plants are male. The best females are
chosen for continued growth during early growth
but after the plants have indicated.
Most fresh seeds have a very high germination
rate, usually about 95%. However, older seeds (more
than 2 or 3 years old) or seeds imported from
foreign countries where they undergo stress
during curing, may not fare so well. They have a
higher percentage of weak plants and they are
subject to disease. Sometimes virtually all of
the seeds from a batch of imported marijuana are
dead.
Intact seeds which are dark brown or grey have
the best chance of germinating. Seeds which are
whitish, light tan or cracked are probably not
viable. Most guide books suggest that growers
plant the largest seeds in a batch, but the size
of the seed is genetically as well as
environmentally determined and does not
necessarily relate to its germination potential.
If the seeds are fresh, they can be planted one
per container. They may be planted in the
container in which they are to grow to maturity
or in a smaller vessel. Some growers find it more
convenient to plant the seeds in small containers
to save space during early growth. Seeds with a
dubious chance of germination are best started in
tissue and then placed in pots as they show signs
of life. The wet tissue, napkin or sponge is
placed in a container or on a plate, and is
covered with plastic wrap. The seeds are check
every 12 hours for germination. As soon as the
root cracks the skin, the seedling is planted
with the emerging point down. Seeds can also be
started in tray pots so that large numbers can be
tried without using much space.
Seedlings and cuttings can be placed in the
refrigerator - not the freezer - to slow down
their growth if it is inconvenient to plant at
the moment. They can be stored in the vegetable
crisper of the refrigerator for a week or more,
in a moistoned plastic bag. The temperature
should be kept above 40 degrees to prevent cell
damage. This does not adversely affect the plant's
later growth, and, in fact, is an easy way to
harden the plants up that are placed outdoors
later. [pH:I have wondered if the plants were
grown in the refrigerator all the way through
picking, and its offspring (from seed) were also
grown in such cold temperatures, if future
generations of the plant would be able to grow,
outside, through winter, by itself.] Seeds should
be sown 1/4 - 1/2 inch deep, covered, and then
the medium should be patted down. Seeds sown in
light soil or planting mixes can be sown one inch
deep. Some growers treat the seeds with B1 or the
rooting hormone, indolebutyric acid, which is
sold as an ingredient in many rooting solutions.
Seeds germinated in covered trays or mini-greenhouses
grow long, splindly stems unless the top is
removed as the first seedlings pop the soil. The
medium must be kept moist.
One way to make sure that the medium remains
moist is to plant the seeds in containers or
nursery trays which have been modified to use the
wick system. To modify a tray, nylon cord is run
horizontally through holes in each of the small
growing spaces. The cord should extend downward
into a leakproof holder. (Trays come with 2 kinds
of holders. Some have drainage holes and some are
solid.) The tray is raised from the holder using
a couple of pieces of 2x4's running lengthwise
which keep tray holders filled with water. The
tray will remain moist as long as there is water
in the bottom. If the tray is to be moved, it is
placed in cardboard box or over a piece of
plywood before being filled with water. The light
is kept on continuously until the seeds germinate.
Most seeds germinate in 3-14 days. Usually fresh
seeds germinate faster than old ones.
Marijuana Grower's Handbook - part 21 of 33
"Early Growth"
Once the seeds germinate, the light is kept on
for 18-24 hours a day. Some growers think that
there is no significant difference in growth
rates between plants growing under 24 hours of
light a day (continuous lighting) and those
growing under an 18 hour regimen. In controlled
experiments there was a significant difference:
the plants get off to a faster start given
continuous lighting. Some growers cut the light
schedule down to conserve electricity.
Plants grown under continuous light which are
moved outdoors occasionally experience shock.
This may be caused by the intense light they
receive from the sun combined with the shortened
day length. Another popular lighting regimen
starts with continuous light. A week after
germination the light is cut back one hour so
that the regimen consists of 23 hours on and one
hour off. The following week the lights are cut
back again, to 22 hours of light and 2 of
darkness. Each week thereafter, the lights are
cut back another hour until the light is on only
12 hours a day.
Whenever a light is to be turned on and off
periodically, it is best to use a timer to
regulate it. The timer is never late, always
remembers, and never goes on vacation. [pH:and
never goes to jail!] Plants are at their most
vulnerable stage immediately after they germinate.
They are susceptible to stem rot, which is
usually a fungal infection and occurs frequently
when the medium is too moist and the roots do not
have access to oxygen. On the other hand, if the
medium dries out, the plant may be damaged from
dehydration. Mice, pet birds, dogs and cats have
all been noted to have a fondness for marijuana
sprouts and the young plants. [pH:everything must
get stoned!] Seedlings given too little light or
too warm an environment stretch their stems. The
long slender shoot subsequently has problems
staying upright - it becomes top-heavy. These
plants should be supported using cotton swabs,
toothpicks or thin bamboo stakes.
Most seedlings survive the pitfalls and within a
matter of weeks develop from seedlings into
vigorous young plants. During marijuana's early
growth, the plant needs little special care. It
will have adjusted to its environment and grow at
the fastest pace the limiting factors allow. If
the plants are in a soilless mix without
additives they should be fertilized as soon as
they germinate. Plants grown in large containers
with soil or a mix with nutrients can usually go
for several weeks to a month with no supplements.
Within a few weeks the plants grow quite a bit
and gardeners thin the plants. If possible, this
is not done until the plants indicate sex, so
that the grower has a better idea of how many
plants to eliminate. The most vigorous, healthy
plants are chosen.
Marijuana Grower's Handbook - part 22 of 33
"Watering"
Growers using passive hydroponic systems only
have to water by adding it to the reservoirs, to
replenish water lost to evaporation and
transpiration. Growers using active hydroponic
systems, including drop emitters, adjust the
watering cycle so that the medium never loses its
moisture. Mediums for active systems are drained
well so that the roots come into contact with air.
Each medium retains a different volume of water.
The plant's size and growth stage, the
temperature, and the humidity also affect the
amount of water used. Cycles might start at once
every six hours of light during the early stages
and increase as the plants need it. Plants
growing in soil or soiless mixes should be
watered before the soil dries out but only after
the top layer has lost a bit of its moisture. If
the mixture is not soggt and drains well,
overwatering is not a problem. Excess moisture
drains.
Plants have problems with some soils not because
they are too wet, but because the soils have too
find a texture and do not hold air in pockets
between the particles. As long as a medium allows
both air and water to penetrate, the roots will
remain healthy. If the roots do not have access
to air, they grow weak and are attacked by
bacteria. Plant leaves catch dust so it is a good
idea to spray the plants every 2-4 weeks with a
fine spray, letting the water drop off the leaves.
Do this before the beginning of the light cycle
so the leaves dry off completely, and the glass
of the lights is not hot in case water touches it.
Some growers spray the leaves weekly with a
dilute fertilizer solution. The leaf has pores
through which the nutrients can be absorbed and
utilized. They claim that the growth rate is
increased. In various tests with legal plants,
researches have affirmed that plants which are
foliar-fed do grow faster.
Once the flowers start forming, the plants should
not be sprayed because the flowers are
susceptible to mold and infections which are
promoted by excess humidity.