Cannabis was one of the first plants cultivated

by humans. Its fibers and seeds have been found in excavations of sites of human

communities that are over 6000 years old The plant has many uses and helped societies

advance time and time again. The symbiotic relationship humans have had with cannabis

probably began when a hunter-gatherer discovered the plant's seed- laden branches. The

seeds are still used as a grain and are easily gathered from varieties which hold them on

the colas (branches laden with buds). The fiber sheath around the stem is one of the

strongest and longest fibers in the plant world It is easily removed from the core after

it has been retted, or left to soak for a while. The fiber was probably discovered after

lying in a pool or puddle. Hemp fiber allowed many human communities to make their first

rope and netting (both revolutionary developments) and then to make the move from animal

hides to plant fiber clothing Humans discovered the psychoactive qualities of the plant

thousands of years ago. The Scythians, who lived in northeastern Europe around 100 B.C,

inhaled cannabis fumes in enclosed rooms. The practices were described by Herodotus, a

Roman, who is considered by Westerners to be the world's first historian. The tribe had

not yet discovered the efficiencies of the smoking pipe. Before recorded history; various

cannabis varieties were developed by a combination of selective breeding and

acclimatization. For instance, people gathering seeds for food would tend to propagate

large-seeded plants whose seeds stayed on the stem. Cannabis usually developed into hemp

in areas above the 30th parallel and contained small but variable amounts of the

psychoactive substance, THC. Hemp does contain large amounts of a nearly non-psychoactive

precursor of THC, cannabidiol, or CBD. The ratio of CBD to THC in cannabis increases with

increasing latitudes of adapted plants. A very hardy semi-weedy variety of cannabis,

ruderalis, is found in the northern Steppes and is still used as a animal food grain. This

variety also has a variable amount of THC Marijuana can be defined as the varieties of the

cannabis plant cultivated for the psychoactive substance THC and its analogs. Marijuana is

one of the most widely distributed plants in the world It is grown in every county of the

United States. Traditionally it has been grown in areas from the 30th parallel N to the

Equator and then to the 30th parallel S. Since the 1960's it's range has been increased to

the 60th parallel. Marijuana and hemp are varieties of the same species cannabis, and are

sometimes interbred to develop new varieties. Most of the chemical and morphological

differences and the extremely diverse gene-pool are artifacts of cannabis's symbiotic

relationship with humans. Humans carried seeds all over the world, and bred the plant to

meet particular needs. This process continues today. Modern marijuana growers are

following in a great tradition. The plant has been re-discovered many times for one of its

products after having been forgotten by previous generations. Americans are growing the

plant today only for its psychoactive qualities. However, there are several reasons to

think that when the prohibitions against its use are eliminated, the hemp plant will also

be grown commercially in the U.S. Cannabis fiber is not only the longest and one of the

strongest in the plant kingdom, but depending on the variety, methods of cultivation,

curing and processing the fiber can be used for anything from ship rope to the finest

linen-like material. Virtually no scientific experimentation has been done on modifying

the fiber for various uses. Yet in countries where its cultivation is permitted, including

France, Italy, and Yugoslavia, it is one of the most profitable crops grown. In these

countries hemp is grown primarily for its fiber, which is used to make paper including

very high quality non-deteriorating stock Cannabis pulp could be used in bio-mass

operations, for paper making and as a substitute ingredient in place of wood fiber. It

would be much more profitable to use cannabis rather than softwood for by-products. Since

cannabis takes only one season to grow, farmers could better adjust plans according to

market conditions. Cannabis actually yields more mass per acre than most forests. Cannabis

seed can be used as a high protein animal feed and also for its oil, which has many

industrial uses. A high protein animal feed can be made from the mash after it is pressed

for its oil. Cannabis is still intimately involved in a symbiotic relationship with

humans. This special relationship will help both species evolve and will continue to alter

both of their destinies. The most important lactor in producing high yielding potent

marijuana is the plant's genes. The goal of the grower is to cultivate a garden of

healthy, vigorous, fast-growing plants which are induced to flower while they are still

short. Indoor marijuana farms are limited spaces. To succeed they must be used as

efficiently as possible. To get the highest yield gardeners grow many small plants rather

than a few large ones. Smaller plants yield more per square foot of space, mature faster,

and are easier to care for than large ones. People used to think that size or age were

important, but they soon found out that maturity or ripeness is the important factor. As

the buds on the plant ripen, their potency increases. Depending on how intensive the

technique and the variety being grown, plants are forced to flower when they are between

8-15 inches tall. Mature plants reach a height of 18-30 inches. Plants forced when they

are small have little chance to develop side shoots. This means that each plant uses not

only a smaller vertical space, but has a smaller radius. Plants which are flowered when

they are very small can be placed very close together. Short plants use much less vertical

space so gardeners often find it convenient to divide the growing area into several levels

of shelves or bunks. Setting up and maintaining a successlul indoor garden requires a bit

of work and some hands-on experience. No one gets the garden running at full potential the

first time out. Any farmer will say: "Don't count your chickens before they're

hatched" Rather than setting up a gigantic sophisticated garden with little

experience, the best growers start off with a less ambitious project which has more chance

of success. Small gardens are easier to maintain than large ones. They take less time, but

more importantly, they do not have the problems of energy consumption, ventilation and

heat that large gardens have. With a small system, the energy consumption does not go up

that much. A large system using several large wattage lamps spins the meter. The heat

created in a small system is easily dissipated into the surrounding environment,

especially during cool months. A large system requires a more sophisticated heat-exchange

system. Marijuana has two distinct parts to its growing cycle. First it grows

vegetatively, then it goes into flowering During the vegetative cycle the plants receive

lighting continuously or for a minimum of 18 hours a day. During the flowering cycle they

receive fewer hours of light. For this reason it is convenient to separate any garden into

two separate units, one for vegetative growth and one for flowering The vegetative growth

unit need not necessarily be large since it is used mostly for starting seeds and clones.

In the most efficient growing system, plants are grown in the vegetative section until

they are 8-12 inches high and then are placed in the flowering area. The vegetative

section requires about ¬ the space of the flowering section. Years ago people grew seeds

from their best stash, mostly sativas, originating in Colombia and Mexico. These plants

grow in a classic conical shape, with long spreading limbs at the bottom and a single main

stem on the top. Since then, Americans have discovered many other varieties such as

single-stem Moroccans, asymetrical indicas, and variants such as "creepers."

There are thousands of varieties of marijuana. They have different potential yields,

highs, flower size, bud structure, ripening time, height, leaf shape, color, bushiness,

and amount of light required for adequate growth. In much the same way that the

environment affects the yield and flavor of grapes, it also affects the genetic potential

of marijuana. The taste, quality of the high' yield, and color are all subject to

modification by the environment Some of the factors include amount and quality of light,

water, temperature, amount, Tatios and kinds of fertilizers or nutrients, and cultivation

practices. The Marijuana Life cyde Marijuana is an annual plant. Each spring the plants

germinate and begin a period of rapid growth. As fall approaches, the plants' growth

changes from vegetative to flowering or reproductive. Female and male flowers are found on

separate plants. To produce seeds, pollen from male plants must fertilize the female

flowers. When the male plants are removed from the garden, the females remain unfertilized

The resulting clusters of virgin flowers are called sinsemilla, which means "without

seeds" in Spanish. These "buds" areprized by the marijuana connoisseur.

Undisturbed by gardeners, the male plants release their pollen into the air; lose vigor,

and die. The female plants continue to produce flowers for quite a while as long as they

remain unfertilized Once fertilized, the small ovary found behind each flower begins to

swell, and within a few weeki, mature seeds are produced when most of the flowers are

fertilized, the plant ceases to produce new flowers. Instead, most of its energy goes to

the maturing seeds. As the seeds mature, the plant loses vigor and dies. The Modern plant

In the past few years the breeders at the Dutch seed companies have popularized new

strains especially bred for indoor growing Many varieties are available which are high

yielding, potent and compact For most gardeners, Dutch seeds are their best choice. while

the price of these commercial seeds may seem costly at first, getting the leest seed stock

is the most inexpensive way to improve a garden. No matter how good the s',stem or

attentive the care of the plants, if they do not have the potential for massive high

quality buds, they will never produce thetft A seed does not represent just a single

plant, but an entire genetic line. New plants are cloned by growers from plants or more

seeds can be produced which carry this heritage. Marijuana varieties are often categorized

as either sativa or indica. Indica plants tend to grow compact with heavy dense buds,

relatively short stature and a minimum of wide branching Sativas used to be gangly, with

smaller buds. Now they have been bred to grow smaller with heavier yields. when marijuana

plants are forced early the new sativas and indica plants gain 25-100 percent height

However the older sativa varieties, even when forced at a short are prized by the

marijuana connoisseur. Undisturbed by gardeners, the male plants release their pollen into

the air, lose vigor, and die. The female plants continue to produce flowers for quite a

while as long as they remain unfertilized. Once fertilized, the small ovary found behind

each flower begins to swell, and within a few weeks, mature seeds are produced. When most

of the flowers are fertilized, the plant ceases to produce new flowers. Instead, most of

its energy goes to the maturing seeds. As the seeds mature, the plant loses vigor and

dies. The Modern plant In the past few years the breeders at the Dutch seed companies have

popularized new strains especially bred for indoor growing. Many varieties are available

which are high yielding, potent and compact. For most gardeners, Dutch seeds are their

best choice. while the price of these commercial seeds may seem costly at first, getting

the best seed stock is the most inexpensive way to improve a garden. No matter how good

the system or attentive the care of the plants, if they do not have the potential for

massive high quality buds, they will never produce well. A seed does not represent just a

single plant, but an entire genetic line. New plants are cloned by growers from plants or

more seeds can be produced which carry this heritage. Marijuana varieties are often

categorized as either sativa or indica. Indica plants tend to grow compact with heavy

dense buds, relatively short stature and a minimum of wide branching Sativas used to be

gangly, with smaller buds. Now they have been bred to grow smaller with heavier yields.

When marijuana plants are forced early the new sativas and indica plants gain 25-100

percent height. However the older sativa varieties, even when forced at a short height may

continue to grow into a large size plant This makes them unacceptable for growing in short

height gardens. Growers have been breeding and adapting marijuana to indoor growing since

the late 60's. Starting with equatorial and indica strains, breeders have produced faster

growing, more potent varieties. Although this work has been done informally, the net

effect of having thousands of breeders working has been the equivalent of a national

program to improve quality. Since the opening of the marijuana seed companies in Holland,

growers in the United States have easy access to many excellent varieties. Some of the

varieties well adapted to closet cultivation are listed below. SKUNK #1 - Developed by

Sacred Seeds and produced by both Seed Bank (SB) and S.S.S.C. It is a stabilized indica-

sativa hybrid with a strong odor and very potent, pleasant high. It is fairly high

yielding and can be grown with high intensity lights indoors. It has a moderate internode

(length between leaves) length. Excellent for greenhouses or skylights. For indoor growers

Skunk is used for hybridizing, NORTHERN LIGHTS- An indica hybrid bred by northwest growers

and popularized by the Seed Bank This variety does very well in grow rooms because of

relatively low light requirements. It is a compact and is easily kept short Northern

lights buds are among the most potent in the world It has quite a distinctive

"personality." It is often hybridized with distinctive plants. EARLY PEARL- An

indica-sativa hybrid developed at a midwestern university. It has a nice, up high.

pleasant taste and is strong, very fast maturing but it has fairly long internodes. BIG

BUD- Avariety with a dense smoke, and indica high. It is very high yielding with a large

bud on a compact plant However it is very finicky; needs a lot of light and is difficult

to clone. It has been phased out of the Seed Bank's catalog but is still being used by

cultivators. All of these varieties have been stabilized a bit They are often hy'bridized

with each other. LIGHT The size of marijuana plants, their potency. even the time when

they produce buds - all these are dependent an the light they receive: its quality,

intensity, and duration, This chapter explains how the photoperiod influences the onset of

flowering, and how it may be used to induce early budding. Before photosynthesis can

begin, radiant energy (i.e., light) absorbed by the plant is converted into chemical

energy. This energy transfer occurs within the unique cellular structures called

chloroplasts. The basic components of chloroplasts are individual membranous sacs,

containing fats, proteins and pigments. Light-absorbing pigments are attached to the

membranes of the sacs. There are several types of pigments; each absorbs different

wavelengths of light. The most important plant pigment is chlorophyll. In green plants,

chlorophyll occurs in two forms: chlorophyll a and chlorophyll b. Both chlorophyll

molecules absorb red and blue wavelengths of light. Green wavelengths of light are

re-flected, giving plants their characteristic color. When sunlight falls on the leaves of

green plants, the illuminating energy triggers the process of photosynthesis. Along with

light and chlorophyll, photosynthesis involves carbon dioxide (C02) and water (H20).

According to current theory on the mechanism of photosynthesis, the chemical energy

produced by chlorophyll from visible light is sufficient to split the water molecules

apart. This provides units of hydrogen (H), and hydroxide units (OH). The hydroxide units

combine with carbon dioxide absorbed from the air, to produce carbohydrates necessary for

plant growth. The hydroxide units also become the source of oxygen molecules, which (along

with water vapor) are released back into the atmosphere. Here is a summary of the

photosynthesis reaction: In the chlorophyllous tissues, both respiration, which occurs in

darkness, and photorespiration, which occurs in the presence of light, are carried on

continuously throughout the life cycle of the marijuana plant. The reaction involved in

respiration is the reverse of that involved in photosynthesis. Carbohydrates produced

during photosynthesis are broken down by oxygen, releasing carbon dioxide and water back

into the atmosphere, and supplying energy for other plant growth processes.

Photorespiration proceeds at a slightly higher rate than does respiration. A measure of

the rate of photo-respiration is called the carbon dioxide compensation point. When this

point is reached, the amount of carbon dioxide given off in photorespiration is exactly

equal to the amount of carbon dioxide taken in during photosynthesis. At the carbon

dioxide compensation point, the net rate of photosynthesis is zero. A plant can increase

in growth only if the rate of photosynthesis exceeds the rate of photo-respiration.

Therefore it is necessary to raise the external concentration of carbon dioxide above the

carbon dioxide compensation point to bring about an increase in the rate of

photosynthesis. (Ways of doing this will be discussed later) Along with the increase in

carbon dioxide concentration, an increase in the intensity of available light reduces the

inhibitory effects of photorespiration. The photosynthetic process is said to be

light-saturated when the rate of photosynthesis will not increase with light intensities

above 2,000 footcandles at normal atmospheric concentrations of carbon dioxide. (Sunlight

on a clear midsummer day is between 12,000 and 15,000 footcandles.) However, if the

concentration of carbon dioxide is increased along with high light intensity, the rate of

photosynthesis will also increase. To satisfy these lighting requirements in a growth

chamber, high-intensity discharge lamps must be used. For most types of plants there is a

direct relationship between the lengths of the day and night periods and the time in the

plant's life cycle when flowering occurs. This relationship is called the photoperiod.

This section will deal with the photoperiodic responses of cannabis, which is a short-day

plant. (There are three kinds of photoperiodism in plants. Short-day plants will flower

with short days and long nights. Long-day plants will flower with long days and short

nights. When plants are day-neutral, the daylength does not have any effect on flowering.)

In 1954 two plant physiologists, H. A. Borthwick and W. J. Skully, were trying to find new

ways to improve crop yields and breeding techniques for cannabis. According to their

findings, when plants were exposed to daylengths of 16 to 20 hours, flowering was

incomplete and was greatly delayed. However, when they received daylengths of 18 hours and

were then switched to daylengths of 8 to 14 hours, flowering occurred in all plants. The

researchers found further that plants between three and five weeks old flowered within two

weeks after being changed over from 18-hour daylengths to 8- to 14-hour daylengths. The

five-week-old plants required fewer 8- to 14-hour daylengths than the three-week-old

plants to produce the same amount of flowering. One of the most interesting observations

related to photoperiodism was the occurrence of "intersexual" flowers on the

marijuana plant. They discovered that when plants were exposed to daylengths longer than

16 hours and then changed over to daylengths of 8 to 11 hours, the production of male

flowers on female plants ranged from 45 percent to 25 percent respectively for the shorter

daylengths. Also, the occurrence of male flowers on female plants that received daylengths

of 12 to 14 hours was greatly reduced or completely prevented. Another important

observation was that when the female flowers were pollinated from male flowers on the same

plant, only seeds that produced female plants resulted. Because of the female plants'

potency, this finding is quite valuable to growers. It would be ideal, of course, to be

able to use the sun as the primary source of illumination. However, most people cannot

afford greenhouses, skylights, or other materials necessary to make adequate use of

sunlight. Growth chambers equipped with highly efficient lighting are an economical

substitute. The most effective source of artificial light found to date is the 1,000-watt

Lucalox lamp from General Electric, a high-pressure sodium lamp. This lamp has a longer

life span, a higher light output, and is more cost-effective than other comparable

high-pressure sodium lamps. It is capable of providing a complete and balanced spectrum.

If this lamp is housed in its reflector and is maintained at a height between two and four

feet above the plants throughout their life cycle, it will produce the high light

intensities required for their growth. Plants use light as energy to tuel photosynthesis,

a process in which water and carbon dioxide (CO2) are the raw materials used to make

sugar. Sugar is the basic building block of all plants. By twisting the sugar molecule,

plants form carbohydrates, which are more complex molecules. Plants use carbohydrates to

build tissue. When nitrogen atoms are inte-grated into the molecules, amino acids are

formed These are eventually grouped together to form proteins. Light is also used to

regulate many varieties of cannabis' reproductive cycle. Scientists speculate that the

plant produces a hormone during the dark period (night in nature) which induces the start

of the reproductive (flowering) cycle. When the hormone builds up to a critical level,

flower growth commences. The number of hours of darkness required to induce flowering

differs for each variety. Gardeners have a choice of lamps to illuminate their garden

Incandescents, tungsten-halogen lamps and screw in "grow bulbs" are inefficient

sources of light. Although they are inexpensive to purchase, their cost of operation makes

them the costliest source of light FLUORESCENTS Until the early 1980's most indoor growers

used fluorescent lights to illuminate the garden These tubes have tremendous advantages

over screw-in incandescent lights. A fluorescent tube emits about 3 times as much light as

an incandescent of the same wattage and has a light spectrum that plants can use more

efficiently. Fluorescents have their limitations. Light is emitted over a large area, the

entire surface of the tube, so it is not concentrated Because the tubes are bulky; onlya

limited amount of light can be delivered to a given area The fixtures are usually placed

within inches of the plants so that the light does not spread and become less intense.

When the light fixtures are hung they are hard to manipulate and make it more difficult to

tend the garden Standard fluorescents have an efficiency of about 30%. Seventy percent of

the electricity is not turned into light but into heat. There are newer types which are a

little more efficent, but the increase in light is of only marginal help. VHO (very high

output) FLUORESCENTS are also available. They use about 3 times the electricity of

standard fluorescents and emit about 2« times the light. While they are not as efficient

as regular fluorescents, each tube delivers 2« times more light to the garden The inner

surface of each fluorescent tube is covered with a phosphor which glows when aided by the

flow of electrons through it. Fluorescent tubes are named for the spectrum of light which

they emit. Some of the spectrums are more conducive to plant growth than others. Deluxe

warm white, warm white, and deluxe cool white are three types which promote fast growth.

Special grow bulbs concentrate light in areas used most efficiently by the plant. However,

they are fairly dim and plant growth is slowed when they are used. HIGH INTENSITY

DISCHARGE LAMPS High intensity discharge lamps (HIDs) are easier to use and more

efficient. Low wattage HIDS are sometimes sold for household outdoor use. Large wattage

lamps are used to light yards, streets, parking lots, stadiums and other large areas. They

come in two versions: METAL HALIDES or MH lamps emit a white light that looks slightly

bluish They are used to light stadiums, convention centers and other large areas where a

natural looking light is desired. HIGH PRESSURE SODIUM or HPS lamps emit a pink or amber

light. They are used to illuminate parking lots and other areas where the color of the

light is not important. HFS units are more efficient than MH lamps. They are often used

alone with no detrimental effect to the plants, and will promote faster plant growth than

MH bulbs during both vegetative growth and flowering Combinations of bulbs are not

required, as the HPS lamp has all the light spectrums necessary for healthy growth MH

lamps come in 175,250,400 and 1000 watt sizes. HFS lamps come in 150, 400 and 1000 watt

sizes. Each lamp has its own ballast. HID lighting systems are much more convenient to use

than fluorescents because the lamps have a higher wattage and are more efficient at

producing light than fluorescents. Large wattage systems are more efficient than smaller

ones. MH lamps have an efficiency of 35-50% depending on the wattage. HPS lamps have an

efficiency of 50-55%. Moving the lamp and reflector is fairly easy since they are fairly

light. The light is powered by a heavy ballast, but it is connected only by a long

electrical wire. Some 400 watt HID systems are manufactured with the ballast built into

the same housing as the reflector. These lamps are harder to move around and are usually

considered for lighting only if they are to be permanently mounted. Because of the ease

and convenience ofoperating a HID lamp and their increased efficiency they are recommended

for lighting indoor gardens. Gardens should receive between 1000-3000 lumens per square

foot. Of course, plants in a 3000 lumen garden will grow faster and flower more profusely

than those under dimmer lights. Successful gardens usually are lit at between 1500-2500

lumens per square foot. During the vegetative stage, plants stretch out when they receive

low levels of light. During flowering the flowers are looser and sparse. LIGHTS AND

REFLECTORS Sunlight comes from a distant source, so that the light rays hitting a small

portion of planet Earth (say a garden 12 feet wide) are virtually parallel Their intensity

does not diminish over the length of a plant 6 feet tall. light emitted from tubes and

lamps travels in all direction. As the distance from the lamp increases, the intensity of

the light decreases. It is not that any light is lost, just that the same amount of light

is spread over larger area HID lamps and reflectors come in two corfigurations. Either the

lamps are held vertically or horizontally: Horizontally held lamps direct most of the

light downward because the light is emitted along the length of the lamp. Only a small

reflector is required to beam the rest of the light downward, Vertical lights emit most of

their light horizontally. In order to reach a garden, the light must be reflected downward

using a large, bulky reflector. Manufacturers have developed elaborate and innovative

hoods, still they cannot reach the light delivery efficiency of a horizontal lamp.

Horizontally held lamps have several other advantages over verticals. They take less

vertical space, which is crucial for short gardens, and the reflectors are much less

bulky. All in all, horizontally held lamps are considered the best corfiguration for the

closet garden. Aluminum reflectors deliver the most light. more than white ones. Stainless

steel reflectors absorb some spectrums of light and should not be used. FLUORESCENT LIGHT

REFLECTORS A garden lit by two tubes per foot of width with a high quality reflector

receives about 1,100 lumens per square foot. A garden lit by three tubes per foot of width

receives about 1700 lumens per square foot. Fluorescents come in many lengths, but the two

most commonly used by indoor gardeners are 4 and 8 ft lengths. They are convenient to use

and are more efficient than other sizes. Poorly designed fluorescent fixtures, with no