Here's something I found interesting, from this article. It appears that weed can flower under surprisingly long days. The flowering phases were identical with 12/12 and the natural outdoor day lengths which varied from more than 14 to less than 12. This may explain why people have flowered with 14 hour days while using end of day far red treatments. I couldn't find any evidence that such treatments are capable of reducing the number of dark hours required for short day plants to flower, though it was useful for increasing stem length.
It's probably possible to flower with 14 hour days even without any far red treatments and the length of time to maturity may not be that much different from 12/12. Can't really tell from this table because at the end the days are less than 12 hours anyway, but I think it's possible. At least they started flowering and kept flowering at the same rate as 12 hours in the early phases, which is unexpected. Since the table shows that florets formed with 14.16 hours, they must have started being induced a week earlier with 14.4 hours. That particular strain, G5, was a high CBD strain, but it may be similar for THC ones.
I'll stick with "We agree to disagree" at any rate.
We can have fun with this.
@Dr. Who We both hold degrees (and from what I gather, both in the "sciences"), and I have read plenty regarding far red. Maybe I missed an article, but I have never read one that asserted a short burst (or even up to 30 minutes) was the equivalent of 2 hours of absolute dark, nor have I read one that asserts that photoperiod during flowering can be extended by exposing the plant to a short period of far red prior to "lights out". I'm very sure the latter doesn't exist as far red doesn't really have anything to do with a plants light saturation point or extending it's ability to utilize "more/extended light" in bloom. It does have some effect on "lights out"/initiating bloom. What some articles do suggest/imply is that far red exposure can help initiate/maintain bloom at the cusp of a plants veg-bloom darkness threshold. For example, theoretical cannabis strain "Dank" requires a bare minimum of 11 hours of darkness to initiate/maintain bloom and any less than 11dark will result in veg/reveg/herm. Our grower wishes to run a 13/11 on/off cycle throughout bloom. This puts our plant in a precarious position, it's literally teetering between reveg/bloom and could switch on our grower at any time. In this example, a brief period of far red exposure "may" help maintain bloom and prevent reveg/herming. This is the equivalent to minutes of "extended" dark, not hours of extended light.
En garde!
