Marijuana Horticulture: The Indoor/Outdoor Medical Grower's Bible

hot-water pipe (radiant heat). You may use a hot frame to raise early seedlings and clones, after which the structure can be converted into a cold frame. Both frames share the advantages of economy, simplicity, small size, and portability.

This carpeted bedroom is completely lined with reflective Visqueen plastic Duct tape works very well to hold the overlapping Visqueen together even under moist conditions.
    Both large and small greenhouses cost more money, time, and space. With the exception of the lightweight “hoop” house or miniature greenhouse, they are also more permanent. The type of greenhouse selected will be determined by the planned use of the space and where it will be located. A leanto or attached greenhouse will probably be smaller and less expensive to build than a freestanding structure.

This Swiss grower anchored a strong steel beam to the ceiling from which he suspended all the lights.
    Total area of the greenhouse is determined by the number of plants you intend to grow. Allow one square yard (90 cm 2 ) per mature plant. Do not forget to allow about six inches (15 cm) space for air circulation between benches and side-walls. Add space for walkways–standing room only or room for a wheelbarrow–and possibly a center bench. Glass, plastic panels, and sheeting all come in standard widths, and it is easier to build in a size compatible with these units rather than have to cut the panels down. For example, an eight-foot (2.4 m) house can be made with two 48-inch (120 cm) wide fiberglass panels. Center height depends on the level of the eaves. Low growing plants can take an eave of five feet (1.5 m); tall plants need six or seven feet (1.8 or 2.1 m). After determining eave height, a simple formula will give you the center height: Center height = eave + 0.25 width (a twelve-foot wide (3.6 m) house with a five-foot (1.5 m) eave will have a center height of eight feet (2.4 m).

     
----
    Necessary Tools:
    Thermometer
    Spray bottle
    pH tester
    Liquid biodegradable soap
    Hygrometer
    Pruners or scissors
    Wire ties
    Sheetrock screws
    Screwdriver
    Measuring cup and spoons
    Pencil and notebook
    Moisture meter
    Light meter
    Yardstick to measure growth!
----
     

These vegetative clones were transplanted a week earlier and grown out under 24 hours of light before being moved into the flowering room.
    Budget, building skills, and security will weigh heavily in the decision making process. The least expensive structure per square foot (m 2 ) is an even-span 16-foot (4.8 m) wide that will house two side beds or benches, two walks, and a wide center bed or bench. An 8 to 12 foot (2.4 to 3.6 m) wide lean-to with wide beds or benches and a central walk is the least expensive option overall. Whichever option you choose, building it yourself will be cheaper and more secure than hiring a contractor. You can purchase much of the plumbing and electricity installations in kits or pre-assembled to avoid compromising security. Here is an excellent web site for the do-it-yourselfer: http://www.buildeazy.com/greenhouse.html Or consider a kit: http://www.greenhouse kit.com/frame.htm .

This cutaway shows the Styrofoam lining to retain heat. The Styrofoam insulates small containers from cold ground. The top is hinged to give complete access and when raised, it acts as an efficient vent.
    Climate will play a role in choosing your greenhouse. For example, a cold frame in the mild Pacific Northwest can give you a six-week jump on the growing season. This would not work in a colder region like the upper Midwest. Likewise, a hot or tropical area will require more shade and water. While the large cold frame is the most economical of structures, it will not function as a cold-climate garden. Location and exposure will depend on climate, but in general, you will want the greenhouse to be sheltered from curious eyes and strong winds and to be away from any areas where falling limbs or other debris might be a problem.

This small greenhouse is covered with corrugated fiberglass. A vent on the top is all the ventilation necessary. Enough light penetrates the fiberglass to foster plant growth and keep out of public view.

Hoop houses are very easy to construct from plastic or metal pipe. Some growers use rebar. Arches can easily be made with PVC plastic pipe up to 8 feet (2.4 m) tall. You can also make tunnels hug the ground with a height of less than 3 feet (90 cm).
    There are a number of external design options. Cold frames can be as