found this somewheres just now:
"I've been pretty intrigued by this theory. Apparently UV light in the early stages of flowering encourages heavy, and early, trichrome formation. I've seen a few side by side grows and the results are pretty interesting. There is definitely a difference between using a UV and not. However there isn't too much info on using UV light in flowering."
and this:
"I believe that trichome production is a form of self-preservation by the plant against UV radiation. Think natural sunblock. There are many, many papers out there supporting this.
Thus it would make sense that UV bulbs, alongside regular grow lights, would increase trichome production. I wonder how a combination of UVB and UVA bulbs would do. I belive you can buy blacklight bulbs that emit mostly in either region: UVB= 290-320nm, UVA= 320-400nm, visible light= 400-700nm, and infrared= >700nm. I definitely wouldn't want to be around the UVB lights when they're on though. That's the stuff you put sunscreen on for.
A big upside to this theory is that the lights are cheap and easily found at pet stores and online. Also they don't require massive amounts of power to run so your electricity bill is not really affected by running them."
and this:
This definitely seems to be the way to go. THC has high capabilities of absorbing UV-B, protecting the plant from the radiation. The idea that the plant would produce more THC to protect it from its presence would seem reasonable. It should also be noted that HPS essentially provides no UV-B, which is most commonly used for indoor flowering. It would definitely seem that there would be a significant opportunity for THC production that is being lost without a source for UV-B.
The reptile lights would probably be the best source. You'd probably need a few unless you found one with a lot of watts (like this one). A tanning light would do it too, but would be pretty expensive I would assume.
I've heard that its best to not leave them on for more than four hours a day because UV-B is harmful to plants, but I would think this is something best determined through one's own experimentation."
also helpful:
I've done a lot of reading about the addition of reptile UV lights in the grow room in the years past. Its best to keep them on a separate timer and have them come on for 4-6 hours in the middle of the photoperiod. So if you on a 12/12 and run the UV Fluorescents for 6 hrs, you would kick them on 3 hours after the lights turn on and 3 hours before them turn off. Most Metal Halide lamps have some UV-B but most of that is blocked by the glass on the cooled reflector.
thoughts anyone? that stuffs all just off forums so who knows?
"I've been pretty intrigued by this theory. Apparently UV light in the early stages of flowering encourages heavy, and early, trichrome formation. I've seen a few side by side grows and the results are pretty interesting. There is definitely a difference between using a UV and not. However there isn't too much info on using UV light in flowering."
and this:
"I believe that trichome production is a form of self-preservation by the plant against UV radiation. Think natural sunblock. There are many, many papers out there supporting this.
Thus it would make sense that UV bulbs, alongside regular grow lights, would increase trichome production. I wonder how a combination of UVB and UVA bulbs would do. I belive you can buy blacklight bulbs that emit mostly in either region: UVB= 290-320nm, UVA= 320-400nm, visible light= 400-700nm, and infrared= >700nm. I definitely wouldn't want to be around the UVB lights when they're on though. That's the stuff you put sunscreen on for.
A big upside to this theory is that the lights are cheap and easily found at pet stores and online. Also they don't require massive amounts of power to run so your electricity bill is not really affected by running them."
and this:
This definitely seems to be the way to go. THC has high capabilities of absorbing UV-B, protecting the plant from the radiation. The idea that the plant would produce more THC to protect it from its presence would seem reasonable. It should also be noted that HPS essentially provides no UV-B, which is most commonly used for indoor flowering. It would definitely seem that there would be a significant opportunity for THC production that is being lost without a source for UV-B.
The reptile lights would probably be the best source. You'd probably need a few unless you found one with a lot of watts (like this one). A tanning light would do it too, but would be pretty expensive I would assume.
I've heard that its best to not leave them on for more than four hours a day because UV-B is harmful to plants, but I would think this is something best determined through one's own experimentation."
also helpful:
I've done a lot of reading about the addition of reptile UV lights in the grow room in the years past. Its best to keep them on a separate timer and have them come on for 4-6 hours in the middle of the photoperiod. So if you on a 12/12 and run the UV Fluorescents for 6 hrs, you would kick them on 3 hours after the lights turn on and 3 hours before them turn off. Most Metal Halide lamps have some UV-B but most of that is blocked by the glass on the cooled reflector.
thoughts anyone? that stuffs all just off forums so who knows?
- ZTELTHY 
