Quote Originally Posted by Zandor
Sorry to disagree with you mack but extra dark will not increase the THC percentage or the chemical content. That is set by the environment and the genetics of the strain.
No apology needed... I love a good, informative discussion! Now here's where I argue, but in the most respectful and inquizitive manner. *grin*

Is the amount of light/dark not part of the environment?

I read that THC production occurs mainly during the dark hours, and that going dark for a few days at the end of flowering will therefore maximize THC production (within the limits of the strain, of course).

I am currently unable to give a source for this info, but if I find it, I'll post it. But I did find similar info right here at Cannabis.com:

Quote Originally Posted by Joel
Leaving your plants in teh dark for the last 2-3 days is a very good technique, while your plants are in the dark they are producing THC.
Not having tested this by putting some branches in full darkness and leaving others on 12/12 then measuring the THC content with a gas chromatograph or what-have-you, I cannot say from personal experience whether or not this is factual... Which is why I didn't say "This WILL increase the THC. I guarantee it!" *wink*

I do know from experience that extra-long nights (longer than 12 hours) will hasten ripening...

So as long as you don't go moldy, extra dark could be a good thing, for one reason or another, eh?