i read in a couple grow guides that if you use hps for veg growth, even though it'll grow slower, the yield of buds will be bigger? any truth to this? has anyone actually tested this?
I've never heard that before. Everthing I've read says MH for veg. HPS for flowering. Right now I have my plants under both while vegging and they absolutely love it.
Hps might be a bit better for flowering but either lamp can be used, and good results obtained, throughout the lifecycle of the plant.
The perfect answer comes from the Cannabis Culture Mag #62 sept-oct issue. On page 98 for anyone that wants to check me it says, "The most efficient light source for both vegetative and flowering stages is the high-pressure sodium (HPS) lamp. Even in their vegetative stage, Plants grown under and HPS lamp grow faster than plants grown Under a metal halide (MH) lamp.