Most of us have head the hypothesis that there is a correlation between higher UVB light and THC production.

One of the main thoughts behind this is that weed from geographic areas with higher UVB is more potent and that the reason is to protect the plant from the damaging UVB rays.

Let's suppose there is merit to this notion. If this is so, it is likely that strains from this region have evolved genetically to produce more THC. But, we also know that UV light damages THC.

So, it might make sense that the way to optimize TCH levels is to grow a plant with high THC producing genetics and then turn off the lights for the last week or so before harvest.

The logic behind this is that evolution has programed the plant to produce high THC levels, but in the process the TCH is likewise degraded by the UV light it protects against.

If this logic holds, the best results would be obtained by allowing the plant to produce a genetically determined amount of THC with no UVB light decomposing that THC. In other words, you turn the lights off a week before harvest to minimize degradation by the UV but the plant continues to produce THC based on genetics.

Scientifically it makes more sense than supplying more UV light that we already know to be damaging to THC. It also makes sense that evolution of a population is more responsible for THC production than environmental factors placed on a single plant. This is basic genetic understanding. Evolution works on populations, not on individuals.

If 'm correct, it's best to turn off the lights a week before harvest.

It works I've tried it with White Widow before in fact it is recommended with white widow during the ninth week to do so...I noticed significant crystal production over the previous week....why would any plant be any different?

I doubt they would. I think THC production is genetically pre-determined much more so than it is condition dependent and will occur on any healthy plant. Plus, I'm also quite sure it takes very little energy for the plant to produce it.

turning the lights off is an old trick, but i think the reason has been forgotten. you know how hydro plants have nice pretty dark green leaves at harvest? people shut the lights off to lighten the color of the buds. dark green turns to light green from lack of light, which is more appealing in a bag than extremely dark buds.

Sounds like a good time to cut the lights is when you begin the flushing process. Plus, less chlorophyll means less lawn mulch smell.

So you are going to have the plants in 168 hours of continual darkness before you harvest?

I think 24 to 48 hours is the standard procedure

I don't buy into this.

If indeed light (or UVB) is the cause for resin glands and thus THC production, then how would darkness increase it???

If anything I'd add reptile UVB lights to my grow room.

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1st grow: BubbleGum & NLX- done and toked.
2nd grow: DP Flo, Magus' Warlock, White Widow and AK-47

It comes from a good understanding of how evolution works. Environmental stress causes a change in populations, not in individuals.

People assume that because potent weed comes from areas of high UVB concentration that it is exposure to the light that makes them produce THC. It is just as reasonable (maybe more so) to attribute this to evolution and genetics rather than exposure of the individual specimen.

It is also just as likely that the THC produced by the plant is an expendable component with regard to the plant's reproductive success. Therefore the UVB could actually destroy THC rather than stimulate it's production.

More simply put - I'm betting the THC production comes from genetics and evolution much more so than environment. If this all holds, you could improve your strain genetics by actually killing 9 of 10 plants with excessive UV exposure and breeding the survivers. After several sets of offspring you should have a much more potent plant.

I know this all sounds complex and that's because it is. Especially, if you don't have a background in biology, evolution and genetics.

Anyway, if all that is accomplished is loss of chlorophyll it's worth doing. Anyway, I hope this makes some sense.

Still no answer...?

So you are going to have the plants in 168 hours of continual darkness before you harvest?