Marijuana Grower's Handbook

by Ed Rosenthal

  When there are legal limits to the number allowed, it is best to grow fewer, but larger plants.

  Some laws and regulations don’t have a restriction on the amount of medicine that a patient can possess but limit the number of plants that can be grown. In this situation, you can grow the plants as single groups that are harvested at the same time.

  It is far easier to grow a garden that is harvested all at once than one in which the plants are harvested at different times. The reason is that all the plants are about the same size and are at the same stage of growth and can be cared for in a uniform way.

  DESIGNING THE SPACE

  No matter how large or small the garden, all of the plant’s needs must be met. The gardener’s duty is to provide his/her dependents with light, water, carbon dioxide (CO2), nutrients, temperature and humidity.

  TINY GARDENS

  You may want to grow but you don’t think that you have enough space. However, even a tiny space such as a small closet, shelf, armoire or portable container can be converted into a garden.

  As an example we will describe the conversion of a closet space to a garden. The closet space has an area of 40" x 22"(100 x 55 cm). It is 80" (2 m) high, divided into an upper and lower space. Each level is 880 sq in, divided by 144 sq in, it equals about six sq ft (0.55 sq m). We will be using only the bottom shelf.

  If the space were to be kept at a high temperature (80°+ F) (27°+ C) and was enriched with CO2 it would be able to use the brightest light, 60 watts per sq ft (650 watts per sq m) This garden space is kept at a lower temperature. CO2 is supplied by exchange with the air in the room. Under these circumstances the plants are not able to use all the light emitted because both temperature and CO2 would be limiting factors.

  The garden temperature will stay in the mid- to high-70s (25° C) and the CO2 will be kept close to atmospheric levels of about 380 ppm. Height is also a limitation to be taken into account.

  Instead, the top level of the garden will be lit using a 200w LED.

  Other good choices for lighting the garden are 250w MH and HPS lamps. They emit about 20,000 and 26,000 lm, respectively. However, without proper ventilation they might create heat problems.

  STEPS TO CLOSET CONVERSION

  For the bottom shelf, the gardener decides to use LEDs as well as CFLs. The total watts used is 199 watts and the light output is estimated to be about 13,500 lumens.

  1.Line the floor with water impervious plastic liner.

  2.Line the sides of the garden including the inside of the door with reflective material.

  3.Install the lights. The lights for the bottom consist of one 14w LED panel of red and blue emitters, two red and one blue 15w LED spotlights and three 85w warm white CFL lamps.

  4.Attach the lights to the metal hanger rod using light fixtures mounted on a clamp.

  5.Plug the lights into a light timer that is plugged into a surge protector.

  6.Install a negative ion generator to eliminate plant odors.

  1. Closet is lined with plasticized reflective material. 2-3. Lights were installed by attaching bowl clamp reflectors to the hanger bar. Six 3-gallon (13 l) containers were placed in a plastic under bed storage tray that fit into the closet and conveniently had wheels. 4. When the door is closed only a sliver of light is visible.

  A few weeks later the plants filled the space and were ready to get sexual, so the lights were turned down.

  GARDEN IN A BOX

  Suppose you have no shelf, closet or armoire to develop as a garden. What can you do? Grow in a box. Not just any box. It should be at least three feet (0.9 m) high, although a taller box would be easier to grow in. This garden was made out of a utility vacuum box. The dimensions are 18” x 18”, 324 sq in, 2.25 sq ft (0.45 x 0.45 m, 0.2 sq m), and it is only 26 in (.6 m) high.

  STEPS TO THE BOX GARDEN

  1.Empty the box.

  2.Create a door. First decide where the door will open. In this set-up, the top will flip open. To make the door three of the four top flaps are cut from the box and the four flaps are taped together using duct tape. One flap is still attached, and serves as a hinge.

  3.Cover the inside of the box using reflective material. It could have been painted using flat white.

  4.Cut four small holes in the top, one in the center of each quadrant, to hold the light fixtures.

  5.Cut two ventilation holes, each 3” x 5” (7.5 x 13 cm), on opposite sides of the box a few inches from the bottom. A 4” (10 cm) round hole is cut into the center of the top of the box to evacuate hot air. The cool air entering and the warm air exiting create an air flow. If additional cooling is needed, place a small inline fan in the top.

  CONSTRUCTING A BOX GARDEN

  1. All the sides are sealed with tape. The top is cut on three sides, leaving one side that opens like a hinge.

  2. Paint the box white or line it with reflective material. The dull side of aluminum foil works well.

  3. Cut holes in the top for the lights and in the side bottom and top middle for air circulation. The hot air will move up and out pulling in cool air from the bottom

  4. The lights are installed. With the addition of a tray at the bottom and plants, the unit is ready to go.

  5. Lights are turned on.

  Rectangular closets with a width of one or two feet and a length of 6-10 feet (1.8-3 m) are easily lit using an HID lamp mounted on a fast moving light shuttle A 400w lamp serves an 8 sq ft (0.75 sq m) garden with dimensions of 1’ x 8’ (0.3 x 2.5 m) or 2’ x 4’ (0.6 x 1.2 m). A 600w lamp can handle a 12-15 sq ft (1-1.4 sq m) garden such as 2’ x 6’ (0.6 x 1.8 m) or 3’ x 5’ (0.9 x 1.5 m). A 1000w or two 600w lamps support a 16-20 sq ft (1.5-1.9 sq m) garden such as 2’ x 8’ (0.6 x 2.4 m) or 3’ x 6’ (0.9 x 1.8 m).

  Fluorescent lights can also be used to light rectangular gardens. T-5 HO or CFL lamps are the easiest to use because they emit more intense light than standard fluorescents. This makes it easier to provide plants with enough light to produce an abundance of Grade A bud. The plants should receive an input of 50-70 watts per sq ft (535-750 watts per sq m). Light a 1’ x 4’ (0.3 x 1.2 m) garden using four T-5 HO tubes, each of which uses 56 watts. Another possibility is to use four 55w CFL fluorescents. Both set-ups work well.

  6.A tray is placed in the box bottom.

  7.Install the light fixtures and hold them in place by fitting them tightly into the holes.

  8.Four 25w CFL’s are installed, three warm white and one cool white are screwed into the fixtures. Each of these lamps emits about 1700 lm for a total of about 6800 lm. Other possible lighting choices are a 100w MH, which emits about 8,500 lm, or a 100w HPS, which emits about 9,300 lm.

  9.Attach light fixture cords to a surge protector and plug it into the timer.

  10. The box is ready for planting.

  THE LARGER CLOSET GARDEN

  One typical closet size is 4’ x 4’ (122 x 122 cm). It is also a convenient building size since building materials such as plywood and plasterboard come as 4’ x 8’ (122 x 244 cm) sheets. This space is 16 sq ft, (1.5 sq m), which makes an excellent size for a productive personal use garden.

  The garden can be set up as it is, or a shelf can be constructed on the bottom for use as a cloning space.

  GETTING INTO THE CLOSET

  Go through the layers of your life as you empty out the closet. This may be a good time to contemplate how lucky you are to be able to start on this glorious project.

  LIGHT

  The garden is perfectly lit using a single 1000w HID bulb. It has an electrical input of about 62 watts per sq ft (PSF). (667 watts per sq m). If a 1000 watt lamp draws too much electricity, light the garden using a 600w or 750w HPS lamp. Either is more efficient than the larger lamp, producing about 90,000 and 105,000 lm respectively, which makes for a very bright garden capable of producing a crop of grade A quality buds. A 400 watt lamp emits about 50,000 lm. Gardens growing under its light produce quality buds but they are not as large or as potent as the buds grown under the brighter l
amps. The garden’s yield diminishes in a fairly direct ratio to the level of light it receives.

  This garden was built in a closet area a little larger than 4’ x 4’ (1 sq m). The bottom shelf, lit by fluorescents housed clones and young plants. The top shelf was lit using a single 1000w HPS lamp. The plants were housed in a reservoir system with 6” (15 cm) square containers.

  This tray of young plants gives new meaning to the term “guest bathroom.”

  The best reflector for this garden is one that focuses the light directly on the plants. Reflect straying light back to the garden using white walls or reflective material placed around the perimeter. Hang the light reflector from the ceiling or structure using a secure fastener. The height of the light should be adjustable. Use link chain, a pulley, or a plant yo-yo. These devices make adjustments very easy. Once the adjustment is made, the plant yo-yo locks at that height.

  Set the timer to provide a dark period during vegetative growth if it is desired. Marijuana doesn’t require a dark period during the vegetative cycle but it may be convenient to turn the lights off when guests are around or when you are sleeping. Later, during flowering the timer regulates the light/dark cycle. You can leave the lights off for up to four hours at a time without triggering flowering. If the light must be left off for a longer amount of time, periodically interrupt the dark cycle.

  TEMPERATURE AND HUMIDITY

  A 1000w HID lamp produces about 3400 BTU’s. Without a bottom glass on the reflector all the lamp’s heat enters the garden. Air cooled reflectors with a glass bottom trap between 66 and 80% of the heat. It is removed from the space using flexible 6” or 8” (15 or 20 cm) tubing attached to both sides of the air-cooled light. An inline fan pushes air through the tubing. One side is connected to a source of fresh air, either from a space adjoining the garden or from outdoors. The heated air has no odor since it was sealed off from the room, so it can be vented indoors or out.

  Prevention of pests and diseases should begin from the time the garden is set up. A hepa filter helps keep the space contaminant free. The Organic Air Hepa Filter traps and filters 90% of molds, insect and bacteria.

  Humidistat/thermostats can be used to regulate fans, A/Cs and dehumidifiers.

  Water-cooled lights remove virtually all the heat produced by the lamp and transfer it to a stream of water in a closed loop system. The water’s heat is dissipated using a radiator or reservoir. Without the excess heat the temperature probably stays in the preferred range, below 80° F (27°C).

  Air-cooled lights remove most of the heat but any excess must be eliminated. When the closet door is open there is a free exchange of air so heat is exchanged with the surrounding air. This is usually an adequate method of cooling. When the closet door is closed light heats up the garden. It may be convenient to turn the light off during this time. If the light remains on, either the heat must be vented out or the air must be cooled in order to maintain excellent garden conditions.

  If the space has a vent at the top the air is removed using an inline fan regulated by a humidistat-thermostat. Another vent, at the bottom of the space, allows cool air to be drawn in as the hot air is pushed out. Whenever the garden gets too warm or humid, the sensor, a thermostat-humidistat, turns the fan on. Air is drawn through a carbon filter to destroy odors, before it is removed. Figure that the fan should be able to draw the volume of air in the space in 5 minutes or less. For instance a space 4’ x 4’ x 8’ (122 x 122 x 244 cm) contains 128 cubic ft (3.6 cubic m). The fan should be able to draw at least 25 cubic ft (0.7 cubic m) of air per minute.

  A small air conditioner can also be used to keep the garden cool. Some small models can be placed above the garden. A 5,000 BTU portable model is sufficient to keep the garden cool.

  AIR CIRCULATION

  Place one or two small oscillating fans in the space to constantly create a breeze from below blowing up through the plants. This pushes out heat from the plant canopy and refreshes the CO2 depleted air with fresh CO2 laden air.

  Set the thermostat/humidistat for maximum humidity of 55%. Keeping humidity under control prevents most fungus infections.

  CO2

  If the closet door is kept open during the lit period and the garden is ventilated, the air exchange replenishes the CO2 as fresh air is blown through the canopy.

  If the closet is kept closed then the air needs to be enriched using a CO2 tank regulated by a CO2 meter. The meter measures the ppm of CO2 in the space and opens or closes the valve accordingly. CO2 is needed during the lit period only, so the valve should remain closed during the dark period.

  Install a 20 lb. (9.07 kg) tank with reservoir. Place it in the closet, or to save space place the tank outside. The CO2 enters the room via tubing.

  Place a waterproof tarp on the floor of the closet.

  Place a carbon filter, negative ion generator or ionizer in the room adjoining the garden. Each has the capability to eliminate the odor. Place a carbon filter along the vent line to clean exiting air.

  THE BOTTOM SHELF

  The bottom shelf is used for cloning and for the development of the plants for a few weeks after they have rooted. During the first three or four days the cuttings should receive about 10 watts of light per sq ft (100 watts per sq m). Then they should receive about 20 watts of light per sq ft (200 watts per sq m) until they are rooted. Once they have rooted, increase the light intensity. The entire shelf is not needed to supply the system with fresh clones, so light should be concentrated in one area large enough to light a 20” x 20” space (122 x 122 x 244 cm). That is large enough to hold two 10” x 20” (25 x 50 cm) trays, which are standard in the nursery industry.

  Construct a shelf about 15” (40 cm) above the floor. It will be holding the weight of the garden above, so it must be sturdy. One-inch plywood (2.5 cm) or sturdy steel gratings both work well. The composition of the wall will help determine its positioning and whether it is free-standing or attached.

  Use two 2' (61 cm) HO T-5 tubes, spaced closely together, rather than spread out.

  T- 8 tubes use 50% less electricity and are less efficient than HO’s—twice as many tubes should be used. Use four tubes to start.

  You can use two 15w CFL lamps, raise the shelf a couple inches (5 cm) to accommodate the length of the tube, which hangs down vertically. Attach the light fixtures to the plywood using metal barriers, and place a plastic barrier between the two.

  THE TWO LIGHT 1000 W OR THE THREE LIGHT 600 W SYSTEM

  Two 1000w or three 600w lamps hang over an area of 4’ x 8’ (122 x 244 cm), 32 sq ft (3 sq m) and conveniently, the same size as many construction materials. There are many ways this unit can be constructed. Remember that you must make the space convenient for you to supply the five essentials: light, CO2, temperature and humidity, water and nutrients.

  Air is drawn from the room, it passes through a carbon filter that deodorizes it, through the lights, and then passes out of the room. Since it is odor-free it can be used indoors or released.

  Air is drawn from outside the space through the tubing to cool the lights and then is released outside the room. The air never comes in contact with the air in the room, so it has no odor. It can be removed from the premises or used to heat another space.

  Starting the garden may be as simple as hanging lights from the ceiling in an alcove and closing off the area using curtains. More ambitiously, you can build a frame using wood or steel and enclose the space in polyethylene plastic, other reflective material, or build the mini-room using plasterboard or other construction material.

  An indoor greenhouse may be the best option for you. These units are easy to assemble, and are designed to install lights and other accessories. Rather than preparing a space you may find it more convenient to use one of these units.

  Two 1000w or three 600w lamps illuminating a 32 sq ft (3 sq. m) space is an ideal intensity to stimulate fast, vigorous growth.

  THE TWO-LIGHT GARDEN

  Construct the structure or prepare the space so the
garden is enclosed. It should have inside dimensions a little larger than 4’ x 8’ (122 x 244 cm) so trays and other tools fit inside easily. Make sure that it has doors or other easy access to the plants. It should be about 8’ tall (2.43 m). This is high enough to be able to hang the lights about two feet (0.6 m) from the plant tops, which can be as high as five feet(1.5 m) from the floor at maturity. The unit should be strong and stable enough to support the light.

  Install the CO2 ppm meter. The tank will be kept just outside the garden space so the sensor’s wiring should be long enough to reach the regulator on the tank. A small tube leading from the tank to the garden supplies the gas to the enclosure.

  1. Four 2” x 4” (60 x 120 cm) boards are placed over two sawhorses; 2: A 4’ x 8’ (122 x 244 cm) tray is placed over the boards; 3: Two air-cooled lights are installed by hanging them from the ceiling—the air intake tubing is placed in the adjoining room and it exits on the other side; 4: Containers on the tray are ready to be planted.

  Several weeks later the plants are basking under the light in their new home.

  Three 600w lamps produce the same amount of light as two 1000w lamps but they use 10% less energy.

  Install the air system. If the garden is to be cooled solely by venting air from a cool place or outdoors, it should have a filtered air intake near the bottom of the unit.

  Tubing should be installed at the top to vent air out.

  Fan: the air should be forced out using an inline fan that moves 100 cubic feet (2.8 cu m) per minute evacuates the air from the a 5’ x 10’ x 10’ (1.5 x 3 x 3 m) space every 5 minutes.