i read last night that many growers are now using uv bulbs for increasing thc from what i learned this really does work,as long as you dont use it too much throughout the light period,i wondered if anyone had tried this,thanks
Lighting uva and uvb
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Mainemedical
Trichome Hunter
I actully just order uvb bulbs for that reason and also to help control my powder mold problem. From what I've read uvb rays can be harmful to the plants so it causes the plants to create more trichomes to protect itself from the harmful rays of the sun. As far as how much to use them I'm not 100% sure but mastereekman has them in his room and he runs them with his regular light schedule. It seems to me like the best thing to do would be to introduce a small amount and then slowly increase the on time. I hear a lot of people saying 4 hours a day works very well
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i had a similiar question re uvb lights but no one seems to have any authoritative research to offer on the subject - it seems to be a case of folks using it cause someone else has
as Mainemedical said, there are some destructive effects, and it does promote the production of a protein "UVR8" (iirc), but putting my "google fu" into 4th gear, i couldn't find anything re THC production. In some plants the production of UVR8 is beneficial, but the main detriment i saw was that it causes DNA damage, so if you're hoping to clone your plant, or if the seed company you got your seeds from used it, it more than likely will cause some strain mutation. The few seeds i've germinated have shown some mutant leaves, irregular shaped and odd numbered leaves and one actually was so convuleted it looked more like a cauliflower, that contorted.
Some plant growth research studies did recommend limiting the uvb light to 15 minutes per 60 minutes so.....
here are some web search results i posted earlier, asking for any research that was authoritative and got zero response, so i have to assume folks are using it cause "xxx" is using it and he's had good results, but nothing clinical to go on
copied & pasted:
"here's one that you might find interesting, it's not one of the ones i'd found earlier and this is not "authoritative" nor board certified in any way, just reports on what Univ of San Fran and Nasa found - apparently there is a wide range of reaction to UV light, by plant by species, and sometimes by strain of a species
http://www.ehow.com/facts_7730297_pl...-uv-light.html
here's the report that UV light triggers plants to producing a protein molecule (UVR8) as a defense mechanism
http://www.scripps.edu/news/press/20...09getzoff.html
and while this isn't the one i had found indicating CFLs emit UV light, it does state it
http://dfw.cbslocal.com/2012/11/05/t...-high-uv-rays/
and another, a little more authoritative, from the FDA on CFLs emitting UV
http://www.fda.gov/Radiation-Emittin.../ucm116400.htm
and while this one isn't the one i had found that the higher temp (5000K and up) CFLs emit some uv light, it does state it, indicating above 4500K
https://en.wikipedia.org/wiki/Fluore...mps_and_health
"The issue of blue or blue/ultraviolet sensitivity has been raised with respect to CFLs and other fluorescent lights at higher color temperatures (e.g., >4500°K)"
and one from budsmag.com re limiting uv light to 15 minutes per hours - again, i am not endorsing nor certifying this one, just reporting it. Interestingly, they do report UV light can be used to increase the THC production in cannabis
http://bigbudsmag.com/grow/how/artic...ht-august-2012 "
as to uvb controlling mold, i thought it was uvc that controlled mold, germs, bacteria etc - haven't found anything on uvb re mold control - but haven't really researched it either
as Mainemedical said, there are some destructive effects, and it does promote the production of a protein "UVR8" (iirc), but putting my "google fu" into 4th gear, i couldn't find anything re THC production. In some plants the production of UVR8 is beneficial, but the main detriment i saw was that it causes DNA damage, so if you're hoping to clone your plant, or if the seed company you got your seeds from used it, it more than likely will cause some strain mutation. The few seeds i've germinated have shown some mutant leaves, irregular shaped and odd numbered leaves and one actually was so convuleted it looked more like a cauliflower, that contorted.
Some plant growth research studies did recommend limiting the uvb light to 15 minutes per 60 minutes so.....
here are some web search results i posted earlier, asking for any research that was authoritative and got zero response, so i have to assume folks are using it cause "xxx" is using it and he's had good results, but nothing clinical to go on
copied & pasted:
"here's one that you might find interesting, it's not one of the ones i'd found earlier and this is not "authoritative" nor board certified in any way, just reports on what Univ of San Fran and Nasa found - apparently there is a wide range of reaction to UV light, by plant by species, and sometimes by strain of a species
http://www.ehow.com/facts_7730297_pl...-uv-light.html
here's the report that UV light triggers plants to producing a protein molecule (UVR8) as a defense mechanism
http://www.scripps.edu/news/press/20...09getzoff.html
and while this isn't the one i had found indicating CFLs emit UV light, it does state it
http://dfw.cbslocal.com/2012/11/05/t...-high-uv-rays/
and another, a little more authoritative, from the FDA on CFLs emitting UV
http://www.fda.gov/Radiation-Emittin.../ucm116400.htm
and while this one isn't the one i had found that the higher temp (5000K and up) CFLs emit some uv light, it does state it, indicating above 4500K
https://en.wikipedia.org/wiki/Fluore...mps_and_health
"The issue of blue or blue/ultraviolet sensitivity has been raised with respect to CFLs and other fluorescent lights at higher color temperatures (e.g., >4500°K)"
and one from budsmag.com re limiting uv light to 15 minutes per hours - again, i am not endorsing nor certifying this one, just reporting it. Interestingly, they do report UV light can be used to increase the THC production in cannabis
http://bigbudsmag.com/grow/how/artic...ht-august-2012 "
as to uvb controlling mold, i thought it was uvc that controlled mold, germs, bacteria etc - haven't found anything on uvb re mold control - but haven't really researched it either
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Ronin
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I run a Quantum T5 Badboy 12 lamp fixture.
10 lamps @6500k and 2 bulbs @10,000 +UVA.
I use them throughout the entire grow.
My thought is, I'm just trying to replicate the sun. UV all day is as natural as it gets.
10 lamps @6500k and 2 bulbs @10,000 +UVA.
I use them throughout the entire grow.
My thought is, I'm just trying to replicate the sun. UV all day is as natural as it gets.
while uv radiation is "natural" it is also a destructive ray - it definitely destroys organic compounds, whether paint, human skin etc - i used to have some apartment buildings, and found flat roofs with black tar, the tar degenerated or dried up and cracked the worst in the sections of the roof where it was exposed to sunlight for the longest period - that convinced us it wasn't the heat on the roof degrading the roof tar but how much sunlight it received.
cars back in the 60s & 70s, the paint would fade depending on color - red was the worst color as it would fade in 2-3 years, and fade badly. Then paint mfgrs discovered adding uv absorbers and uv blockers to the paint helped the paint color resist fading - google for em, Ciba Geigy (swiss chemical company) is the predominant supplier of uv absorbers, but once added to the paint, it lasts a helluva lot longer. Today, car paint goes quite a few years more before it starts to fade.
that's why i was looking for the source that proved uvb was a beneficial thing for cannabis or thc production
btw, uv absorbers are what make flourescent paints "glow" - uv absorbers take uv light and refract it and then reflect it back out in a wavelength of the spectrum of light that is visible to the human eye, that's why surfaces painted with flourescent paint appear to "glow" ie give off more light than they appear to be receiving
back to the point, if all folks are basing their decision to use uv light is the fact that "xxx" got great results, i've got to ask, how do we know those results wouldn't have been better without the uv spectrum hitting those plants?
plus, if you check some of those links i posted above, serious research has shown that CFLs above 4500K emit uvb radiation
cars back in the 60s & 70s, the paint would fade depending on color - red was the worst color as it would fade in 2-3 years, and fade badly. Then paint mfgrs discovered adding uv absorbers and uv blockers to the paint helped the paint color resist fading - google for em, Ciba Geigy (swiss chemical company) is the predominant supplier of uv absorbers, but once added to the paint, it lasts a helluva lot longer. Today, car paint goes quite a few years more before it starts to fade.
that's why i was looking for the source that proved uvb was a beneficial thing for cannabis or thc production
btw, uv absorbers are what make flourescent paints "glow" - uv absorbers take uv light and refract it and then reflect it back out in a wavelength of the spectrum of light that is visible to the human eye, that's why surfaces painted with flourescent paint appear to "glow" ie give off more light than they appear to be receiving
back to the point, if all folks are basing their decision to use uv light is the fact that "xxx" got great results, i've got to ask, how do we know those results wouldn't have been better without the uv spectrum hitting those plants?
plus, if you check some of those links i posted above, serious research has shown that CFLs above 4500K emit uvb radiation
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Hello, In answer to that I would say that I used 1x26w and 1x13w UV10.0 reptile CCFL lights, and on the same big plant, the buds closer to the UV lamps where stronger in effect and more cerebral/active, so I think it does increase THC production. Both lamps were a few inches away from the plant and the area close to the lamps didn't seem to suffer, if anything that part seemed healthier.. Lamps were on a 20/4 cycle as the rest of the lighting system.
I'd say one should use at least 20% of the power of the HID lamp in UV (i.e. 1*400W HPS +4x26W UV) lights to cover the same area with UV. Does anybody know if a Mercury Blacklight would be harmful to the plants? Would it be better than CCFL Reptile lamps for THC production?
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