Quote:
Originally posted by JoséHempSeed
and i'd buy that book, too.
i can tell you this: all light bulbs with glass envelopes put out virtually no uv. Tthat's because glass is a uv filter - everything below about 300 nm is filtered out by the glass.
however, there are uv lights - like the gremicidal lamps - that have quartz or ceramic envelopes. you can get plenty of uv from them. but they're pretty expensive.
so i'm not sure...even if we knew how much uv we needed...if we could even do anything about it  except, of course, grow outdoors! 
there is a simple experiment that would tell us if it even is the uv that makes outdoor grows better - grow a crop in a greenhouse, and next to it grow an outdoor crop. then you'd have a pretty good control, the glass would filter out the uv on the greenhouse side...anybody have a spare greenhouse? |
Not trying to take this even further off topic but I think UV has more to do with the production of psychoactives within cannabis than anything else; acting as a counter/shield to negative UV effects. I don't think UV is generaly very good for plants which is why its not already included in general horticultural lighting. Thats what makes cannabis growing special in this regard- the more UV (b) and theoreticaly the higher production of the goal of the grow: the psychoactives.
I would ouble warn anyone attemptin to take the outer envelope off of their (mv) lights...and not just from the point of the light its self but also from the leaking of gases within the bulb that are otherwise double-sealed in. Saftey first, especially that of your family and pets
