12/12 schedule ruined by 15 minutes, stress?

The 12-12 formula has been accepted without question by growers all over the world. Probably one of the reasons for this was my discussion of the technique in some of my early books. The 12-12 regimen was selected because my co-author and I reasoned that no matter what critical period a variety might have, given 12 hours of darkness it would flower. However, most marijuana varieties need fewer than 12 hours of darkness to flower.
If marijuana plants grown outdoors required a 12-hour dark period to flower, they would not be induced to start flowering until September 21, the first day of autumn, when day and night are equal length. They would ripen 6-8 weeks later. In real life most modern varieties ripen between early September and late October. Budding was triggered 6-8 weeks earlier. For instance, an eight-week variety that requires 55 days from forcing to maturity, which would normally ripen on October 1st, would start flowering August 1. At that date in San Francisco, sunrise occurs at 5:14 and sunset at 19:18, a total of 14 hours 4 minutes. Dawn and dusk add another 15 minutes of red light. Plants use the absence of this spectrum to measure the dark period. The total lit period came to about 14:20, leaving 9:40 minutes of darkness. The critical period for this plant was 9 hours 40 minutes. If it were given just 10 hours of dark period daily indoors, rather than 12 hours, it would still flower.
Gardeners growing outdoors who discover the critical time needed to induce flowering can use this information to get more efficient use of their indoor garden. Currently, plants grown under a 12/12 cycle spend half their time in the dark. If the plants have a critical flowering time of, for instance, 10 hours of darkness daily, they can be provided 14 rather than 12 hours of light each day so that they receive almost 17% more energy which they use to produce sugars used for more and faster growth.

Click to expand...

charface said:

you can go with it or just change it back.

Click to expand...

Cascadian said:

I know some growers use 13/11 with success so 12/12 isn't necessary. 15 minutes on one day will barely be noticeable to the plant. I would go ahead and resume your preferred schedule. Great point on real world light/dark flowering times.

Click to expand...

When blue light is turned on during the dark period, plants photosynthesize but their flowering isn’t affected. This results in more growth as the plants produce more sugars. Before LED lights it was difficult to create a pure blue light. Instead, most of the time other spectrums were filtered out, which can be an inconvenient process. Try using between 20 and 40 watts of mixed blue light per 1000 watts of regular light. I have done only initial experimentation with this so test this in a limited way first. I suspect that the additional light is an efficient way of increasing total yieldAside from red and blue light, plants also use orange light for photosynthesis. I haven’t experimented with them yet, but orange LEDs might also help increase yield and probably can be lit continuously, just like the blues. More on this as the news breaks—or at least, as it fractures.

Click to expand...

direct said:

I'm growing barney's LSD, liberty haze and dinafem cheese. hoping those are good enough genetics to not hermie from something this little. i think i'll just leave it alone, don't want to keep tampering with the timer and it is 12/12 now so shouldn't make too much of a difference (hopefully) -- you seem to have been here long enough for me to trust you

Click to expand...

lushgreen said:

Just leave it, as said, it won't make any difference. Smack the shit out of your room mate for touching your grow though.

Click to expand...

Mikelej14 said:

So Similar situation, kinda, but, different:
My timer is set 9pm-9am to be off, but last night i had forgot to close up the area for light, so it turned off normal time, but may have had some minor light leakage for about an hour until another door got closed...
Do you think that happening will cause any issues?

Click to expand...

Mikelej14 said:

Lol wow sorry didnt notice it was so old, strange that it was shown to me at all as if it were recently posted.. but none-the-less, old or not, still applies thanks for quick response i try not to let it happen, i have my area closed up in back of a deep walk-in closet, but that area i made isnt 100% lightproof, so i also have a heavy blanket hung over the closet area to block light the reflected/indirect bedroom light from going in that closet. Just forgot to flop the blanket back down

Click to expand...

jondamon said:

You should be fine.

plenty of people go in their rooms and take pics during dark hours.

just don’t make a habit if it. .

Click to expand...

Mikelej14 said:

Hah I do have to say that is the single hardest part of 12/12 cycle.... Staying out and leaving them alone ahaha

Click to expand...