Best time of day for 12/12 cycle

Hello all, this is a basic question but I could use some advice. I didn’t see this question anywhere so here I am.
I am about to start the first 36 hours of complete darkness for the girls and then it’s 12/12.
My question is, what is the best time of day to start the 12/12 cycle? I’m thinking to start the dark at 6 am and the light on at 6 pm. What do you recommend? Thanks.

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It’s more a matter of individual preference rather than the “best” time to do it. A lot of people run their lights during the daytime. Others who have issues managing heat in their grow space will run their lights during nighttime.

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Like Midwestguy says its really up to you. There is no benefit or drawback to any particular time.
I go lights on at 6am and off at 6pm. For me its because tending to , watering and such are done thru the day so its right for that. Also overnight insures its got good dark hours without light creeping in.
But someone may work all day and need time to do those things in the early evening so they might go 12 pm to 12 am.
Must consider how dark you can make the room during daylight hours if you do lights out at those times. Not particularly hard, but something to consider.

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I run my light on at night in the summer it’s the hottest time of the day I vent my tent outside and in the winter it’s the coldest time I vent my tent in the house to use the heat

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And some of us even run them all the time​:rofl::rofl:

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Yep. Though I wasn’t thinking about autoflowers.

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I find running my light during the day and I will get nothing but gardening done (GAZER, big time). 9am until 9:30 pm I get my coffee with the ladies, have time for some tent or plant working and then go about my day. Conditions in the sleeping flower tent are monitored and the DND sign is out. Evening time when light come on, I can spend time with them before my lights out. No more trips to the tents at 3AM to check temps. I just put the flower tent to sleep and reduced intake fan. 5-minutes later the RH hit alarm pre-set 75%, so I upped the intake to #3 speed. Still quiet and efficient at proper needed level inside the tent.

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@dirtydave has the best reason for night lighting, being cooler atmospheric temps

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Yep. Exactly this. My AC already has to work hard to combat 100°+ temps, I don’t need to add the heat from my lights to that.

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I run mine on from 9:30am to 9:30pm.

9:30pm is more-or-less my weekday bedtime, so I set lights-off when I know I’ll no longer be doing maintenance.

Unfortunately, my party-like-a-rockstar days are in the distant past.

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Pre flip?- that’s a new one for me. I just change them. On and off times is a matter of convenience for me and also heat management. I am a morning person so lights are on in the morning no matter what.

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Why? What is the theory behind this? I can’t think of one.

As for best hours for 12/12… If you don’t have a personal preference, then have the lights on when the area is coolest. This will help manage temperatures.

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I’ve read about it before. I think the theory is that since the plant’s flowering response is tied to period of darkness, that an extended period of darkness at the transition will cause the plant to produce flowers faster.

That said, my current photo is my only photo and I didn’t do this. It did, however, get about 18 hours of dark in the switch from 16-8 to 12-12. I saw signs of flowering in a couple days.

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Light is the engine of plant growth. Just seems wrong to remove that engine…

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i was just reading this in the garden culture magazine (freebie from autopots) and it says

sorry for reverse order. cant change on phone right now

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I’m thinking electricity wise it would be better to run the lights during the night hours. I’m in Florida so hot here most of the time. So dealing with outside heat and grow lights indoors, it can get pretty HOT. I have to run the AC to keep the heat down so I figure lights on at night when its slightly cooler.
Thanks for the advice and opinions, it’s much appreciated.
BTW Just planted to beauties outdoors… let’s see how that goes with this dysfunctional summer Florida weather. I heard it sucks, makes me miss California.

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I’m just following the theories haha I don’t understand how or why they work, but Alexankh posted some good info.

I run mine at 930am on , 930pm off.

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I just read an interview yesterday of DJ Short, father of the “blueberry” strain. He was asked to give 1 piece of advice and it was to run 11 on, 13 off for flower.

I also run mine at night, year round. Except the summertime; we’re gonna go play outside.

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