The Marijuana Horticulture Bible is a great book! I have a closet space 3 feet square by 4 feet tall. I want to grow 2-3 plants in this area. How many HP sodium watts should I use to get a good amount of finished product? ROXY F
Good question. How much light is too much? How much light is enough? You can use anything from 150 to 400 watts to have an adequate harvest that will keep you in smoke. The light does not necessarily have to be generated from a HP sodium lamp. However, I suggest growing a few more plants. Grow at least 6 plants and possibly as many as 18 in the room. Growing more plants will ensure that you have a good harvest. If you have disease, pest or cultural problems and are growing only 2-3 plants, they could get wiped out quickly and you would have to start over. If you grow a dozen or more plants, you can easily pull some of them if they are too big for the closet and still get a strong harvest. It is much easier to pull a plant than it is to wait for a new one to mature.
I just returned from visiting many grow rooms in the Netherlands. Most of the rooms were illuminated by less than a dozen 600w HP sodium lamps. Growing marijuana in Holland is illegal and many grow shows are busted every year. Growers seldom spend any jail time, but are given fines and their equipment is confiscated. One of the main ways growers are caught is by power consumption. The less electrical power consumed the lower the chance of being found out. Several growers in Southern Holland were growing with half as much light as they were before and harvesting about 85 percent as much weight as when they used double the amount of light.
The premise is simple. If you have two lights, turn one on for two hours and keep the other lamp off. At the end of two hours, reverse the order; turn one light off and the other light on. Continue this regimen for 12 hours so that each lamp is illuminated for a total of 6 hours at two-hour intervals. I’m not exactly sure what all happens within the plant when it is given strong light for two hours and less light for two hours. I will have more information on this subject later. I did see plants growing under this light regimen and doing quite well. The buds were well formed and fairly compact. Everything I saw led me to believe the light regimen works just like all the growers that I spoke to said it did. I will know more in another month when I return to visit the same grow rooms and weigh in on the harvest.
There are quite a few other benefits realized by using half as much light. Temperature and humidity are much easier to control and maintain at acceptable levels. Summertime growing in hot climates would make vast improvements using such a regimen of light.
So to answer your question about light, I suggest using four 65w compact fluorescent lamps. Hang the lamps overhead in a matrix pattern so that each lamp illuminates approximately one quarter of the grow area. Turn two lamps on for two hours. At the end of two hours, turn two lamps off and two lamps on. Continue with this regimen for 12 hours each day. You will be using no more than 130 watts and be growing the absolute maximum amount of smoke for the amount of light you are using.