Does it matter what bulb i by for my 400 watt mh grow lamp. I can buy the bulb for like 15 bucks but then i see some that are like 80 bucks. does it matter what i use.
Anybody heard or know anything about mercury vapor lights? They seemt o be cheaper than mh or hps, I'm wondering if they produce the correct spectrum of light for growth?
This is the first time i have grown indoor, and my stems are very small im afraid when the plants get bigger they will just fall over, any suggestions on fattening up my stems?