Sometimes it is advantageous to put your grow operation in an out of the way place such as a basement or cellar. While the location might be good, you have to ask yourself a few questions about the environment local to your plants. Is it too hot or too cold? Cannabis is of tropical origin, so most places you put your crop at can be very warm. The cold, though, can really mess up the metabolic rate of your plants. What does temperature have to do with lighting, you ask? Read on.
The mercury vapor lamp is a great addition to any cannabis grower’s arsenal of tools. It emits a visibly blue light, which is great for the foliage growth stage. The greatest advantage that the mercury vapor lamp brings to the table is simply heat. That’s right. Lots of light and lots of heat. So much heat, in fact, that if you were to use a mercury vapor lamp to grow your whole crop within a room temperature environment the plants would die of heat stroke within a few hours.
We’ve all seen set lights in the movies or on TV. You might have also noticed that those people who are under those lamps are sweating profusely. This is because the lamps being used are mercury vapor lights and they emit lots of heat.
The mercury vapor lamp is used when the grow area is cold. You can use more than one to add more light and more importantly more heat to the growing area. You would use these lamps much the same way as you use any other high intensity discharge lamp. Because they do emit lots of heat they have to be further away from the plants so as to not scald them.
Another consideration is the metabolic rate that the plants are operating at. A normal temperature of 22 to 24 degrees Celsius is the best for cannabis. If the plants get too cold they’ll begin to shut down and will refuse to grow at the rate you might be used to. If the temperature lowers during the night the plant will take up a quick sip of nutrients from the root and stop growing. After the lights come back on the plant will awake after it warms up. This usually takes a couple of hours.