Posted – July 1st, 2010
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Maybe you're tired of paying top dollar for weed or you want to make some extra money, but where do you start? This guide assumes you have no prior knowledge whatsoever of growing marijuana. It is not intended to be a complete guide but rather an overview of everything you need to get started. The concept assumes you are growing indoor but some of the concepts can be applied to growing outdoors. If you have ever cared for a house plant you have most of the knowledge you already need to care for a marijuana plant. Marijuana like all plants require these simple things:

*Fresh Air


Marijuana like nearly every other plant starts is started from seed. The plant will sprout out and grow very vigorously to about 2' within 1-2 months. During this time the plant is exposed to 18 hours of light and 6 hours of darkness. This is known as the vegetative state because the plant is concentrating all of its energy into producing leaves, stems and roots. When the plant is about 2' tall the light cycle is changed to 12 hours of light and 12 hours of darkness. This is known as the flowering state because now the plant is concentrating all of its energy into producing buds. This stage lasts 4-12 weeks. After the flowering stage the plant is harvested and dried.


All plants require light and food for a process called photosynthesis. Photosynthesis is the process in green plants by which carbohydrates are synthesized from carbon dioxide and water using light as an energy source. Photosynthesis release oxygen as a byproduct. Fortunately we only need very modest information about photosynthesis to be successful!

The best type of light for plants is always the sun. The sun is much more powerful than any artificial light. When growing indoors requires we use artificial light rather than the sun but fortunately it has some very important advantages:

*You have a lot more control over lighting cycles and can have multiple crops per year
*Unaffected by different seasons and weather conditions

If you are growing indoor and using artificial light you can never match the actual light output of the sun – therefore you want as much light output as possible. Standard incandescent bulbs (most commonly found in house lamps) are too inefficient at converting electricity into light output for growing cannabis. Although marijuana can be growing using fluorescent lights for best results a HID (High Intensity Discharge) lighting system is highly recommended. There is two types of HID lighting systems are are suitable for growth: HPS (High Pressure Sodium) and MH (Metal Halide). HPS systems are more efficient for the flowering stage and MH are more suitable for the vegetative stage.


Marijuana is a very fast and vigorously growing plant (they don't call it 'weed' for nothing). To ensure it is growing at its optimal potential it is important that you supply it with a constant supply of fertilizer. Fertilizer should be added to the plant about 2 weeks after it has sprouted from the seed and applied until 2 weeks before harvest. The last 2 weeks of harvest where only water and no fertilizer is added is called “flushing”. Flushing is done to remove the excess fertilizer from the plant and to improve its quality.

Fertilizer is such that “you get what you pay for”. Using low-cost generic fertilizers is discouraged in favor of using quality fertilizers designed specifically for growing cannabis. The amount and frequency to fertilizer your plant is specific to the individual type of fertilizer you use. Consult the instructions on the label for specific feeding instructions.

Fresh Air

In addition to light and food C02 is required for photosynthesis to take place. Within the air we breathe there is enough C02 for the plant. Plants through the process of photosynthesis use C02 and convert it into oxygen. If the air in the room is not constantly replaced with fresh air the plants will suffocate and not achieve optimum growth. Ventilation will also keep the grow room at the proper temperature (70-80° Fahrenheit) by cooling the room.

To achieve this your grow room must have some sort of ventilation system. Usually this is achieved with an INPUTOUTPUT ventilation channels. The air is moved via one or more fans. Input ventilation channel is fresh air that is usually taken from outside. No smell is transmitted from the input channel because air is being pulled in. Air is expended via the output channel. The output channel will also remove excess smell and heat generated from lights. and

The output must must take into account the odor produced by the plants. Odor is one of the most common ways grow ops get discovered. Fortunately there is several methods for dealing with the expended air. The first method is by deodorizing the air by using either a charcoal filter or ozone generator. It can then be safely vented back outside without raising suspicion of a grow op via odor. The second method is by venting the expended air to either the sewer system (by taking out the toilet) or through the bathroom or oven vents where it will go through the top of the building and up into the atmosphere (hot air rises).