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uva light to enhance tricomb production

Been reading this for the past couple of days. Was also planning on running 2 4' T5's agromax on my grow. My plan was to run them a couple hours before the end of the light cycle. Did not know that it would lower your yields or the fact that your not running them for more than 15mins at a time. Or the fact that it will speed the harvest. Going to have to give this some more thought. I have one plant in my grow that I call "lettuce head". Although all the seeds came from the same packet, ain't nothing the same about this 1 plant. Its also a week behind in the flower stage. Maybe I'll just get a couple of 2'ers and torture that one LOL.

Glad I got on here, you just can't go talking about your "hobby" with anybody
 
D.A.A.S.69 Hey how long are the bulbs guareteed for? They cost good money, and if it burns out in 3 months or so its not worth it. I couldn't find any info. on this.
 
Like Potted said, it's the on and off,
I've had mine 2years and it's still doing fine.
I hope that helps some.
If you are gonna grow, cheap lamps-bulbs, don't cut the mustard.
Good Luck with whatever you use, but don't ever buy the cheap lamps-bulbs.
 
Oh no I totally aagree, I'm going to buy the same as you have, I was just wondering the length of the bulb life. I'm a firm believer that you usually gget what you pay for.
 
I have not used UV whichever its flavor, nor am I Doctor Photon, but I would think it best to emulate the spectrum of natural sunlight as it falls upon the earth. The cannabis plant has evolved through natural selection, and fine tuned itself to this natural light source. Below is a chart showing which UV rays actually penetrate the ozone layer, and which do not. Therefore I would say that UV A would be beneficial to resin production whereas B and C might be detrimental. Maybe DrPhoton can clarify this for us. [TABLE="class: wikitable"]
[TR]
[/TR]
[TR]
[TD]Ultraviolet A[/TD]
[TD]UVA[/TD]
[TD]315–400[/TD]
[TD]3.10–3.94
(0.497–0.631)[/TD]
[TD]Long-wave, black light, not absorbed by the ozone layer[/TD]
[/TR]
[TR]
[TD]Ultraviolet B[/TD]
[TD]UVB[/TD]
[TD]280–315[/TD]
[TD]3.94–4.43
(0.631–0.710)[/TD]
[TD]Medium-wave, mostly absorbed by the ozone layer[/TD]
[/TR]
[TR]
[TD]Ultraviolet C[/TD]
[TD]UVC[/TD]
[TD]100–280[/TD]
[TD]4.43–12.4
(0.710–1.987)[/TD]
[TD]Short-wave, germicidal, completely absorbed by the ozone layer and atmosphere[/TD]
[/TR]
[/TABLE]
 
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This is a most interesting, I’m enjoying the bantering as this subject has perked my interest and am always looking for ways to up my game😁
 
Natural sunlight, as it touches earths surface, has verifying amounts of UV light depending on where you are taking the sample. Example: the equator naturally has more UV than the north and south poles do. Also, the higher elevation locations naturally receive more UV light than lower elevations do.
 
Greenleaf You can always, try to talk them down some, I know I did, but I've bought a bunch of stuff from them before too, but it doesn't hurt to try, I sure would.
I hope you have as good of luck with yours, as I do with mine !!
HappyGrowing.
 
Many older studies including the 1987 by john lydon, have shown that UV-b has a direct effect on cannabinoid synthesis. Mainly THC. But this paper has created confusion as it does not consider or discuss about the possible effects other wavelengths of light has on cannabinoid morphology. So many assume that its only UV-b. Most recent studies have shown that it likely is not just UV-b but also UV-a which can stimulate THC biosynthesis and manufacturers like black dog have made their own conclusions through their research that UV-a is as effective. And now include that spectrum as apart of their products.
 
Of course especially at higher altitudes. But it would seem from the above chart that most of B and all of C are just not there. Probably would only be detrimental to the plant. B would most certainly damage the plant, and C probably kill it.
 
I imagine that is the reason for periodic lighting to stimulate, but for not long enough to do any damage, or less damage. I'd hate to give up yield for a bit more THC, and has that even been quantified?
 
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Although it is likely that photosynthesis is affected by UV, this does not mean it difinitively effects yield. As how light is utilized from a whole plant point of view, is different from looking at the individual effects on leaves. For example, it has been shown that even when one plant has significant lower levels of chlorophyll in leaves over the whole plant compared to another. This does not affect the total light utilization as the light which does not get absorbed at the upper canopy, filters down and is eventually absorbed by lower level leaves. As such the load is shifted where the majority of the photosynthesis occurs, but the total light utlized is unchanged.

The recent study which i cited however does show significant degradation of flower yield so evidence does point towards UV lowering yield through reduced photosynthesis.
 
UV b is what causes increases in oil production. UV b causes damage to DNA in plants and animals. THC production builds a barrier to protect the plant’s buds from UV b damage.
Even if you remove most of the UV spectrum, the plant will still create THC (like it is genetically told to do). But THC would be greater in quantity if UV light was used.
I hear what you are saying about what is found in nature...but...Let’s not forget that when things were left up to nature max THC was like 5-8%. When human intervention occurred, we are now seeing strains that are capable of producing 30 plus %.
 
DrPhoton Yes sir you are correct. I'd like to find a copy of that 1987 book by John Lyndon but it seems very hard to find, if you google the name the only John Lyndon that comes up is the lead singer of the Sex Pistols (Johnny Rotten). Everything I've read so far concurs, that UVB raises total cannabinoids but lowers yield.
 
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