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12/1 lighting--Any truth or banana in the tail pipe?

softyellowlight

Active member
So why 12 on 5.5 off 1 on 5.5 off? Why not something like 7 on 3 off 6 on 6 off? It all seems rather arbitrary, but I mean, so does 18/6 and I'd rather try something different this next cycle if other people are seeing benefit.
 

GanjaPharma

Member
So why 12 on 5.5 off 1 on 5.5 off? Why not something like 7 on 3 off 6 on 6 off? It all seems rather arbitrary, but I mean, so does 18/6 and I'd rather try something different this next cycle if other people are seeing benefit.

hmm. i think i read the manual wrong. i have been doing 12 on 5 off 1 on 6 off.

no problems at all...see my earlier post, i love this veg method for all sorts of reasons. just wanted to clarify what i have been using.

oh and directly to your question. beyond the botanical considerations, I think the 12 hour intervals offer an ideal solution for summertime grows that wanna burn only at night, for someone who wants to use a flip and run a veg.
 

blueberrydrumz

Active member
ICMag Donor
hmm. i think i read the manual wrong. i have been doing 12 on 5 off 1 on 6 off.

no problems at all...see my earlier post, i love this veg method for all sorts of reasons. just wanted to clarify what i have been using.

oh and directly to your question. beyond the botanical considerations, I think the 12 hour intervals offer an ideal solution for summertime grows that wanna burn only at night, for someone who wants to use a flip and run a veg.
yeah i dont think it matters aslong as you brake up the night cycle... should be fine
 

wildgrow

, The Ghost of
Veteran
Ive been vegging for 3 months under flouro tubes. I sexed them after 2 months. They are still spitting out preflowers, so Id be weary of going to a 12/1. I think anything less than 14 total hours of light would send them into bud. However, I do think if I ran 14/1 my plants would keep pushing pistels w/o completely going into bud. That would be 14 on, 4.5 off, 1 on, 4.5 off. What does everyone think would come of this schedule?
I do like the idea of decreased lighting in flower. In fact, I have mentioned to a friend that he run his bud room at 10/14 to try and finish off a jack herer thats at 10 weeks and still piling on fresh flowers. Do you (collectively) think this will help finish it? Also with a 2-3 day total dark period before harvest? Cheers
 

Phaeton

Speed of Dark
Veteran
I read the science behind it, the idea is simple just lots of steps involving chemicals with long names.

The hormone the plants builds up in the dark to cause budding is reversed by red light, the process needs far red light to operate. The plant converts red light energy to far red and vice versa, a shot of red restarts everything, absolutely preventing budding.
Same process that allows light leaks to kill budding.

Only takes minutes of light leaks to restart veg, full on bud lighting completely and totally restarts the plant within 20 minutes.
Using a full hour is less stress on the lighting system, bringing the lights all the way up to temperature is better than turning them off still cold.

Started the 12/1 system last june, growth in veg has been dialed in.
I have a new budroom only two months old. I am measuring both the sativa and indica going in. 12" will be the number, the sativa is almost there, the indica will take another week. Eight plants have come out of the room, it works well.

I have been growing the sativa for 4 years and the indica for 9 months. I have interupted the 12/1 enough times to know the stretch by eye. This time there is a yardstick on the plants.

The whole point of 12/1 is the reduced light without budding, my indica wanted to bud starting at just over fourteen hours of light. Now I get solid unchanging preflowers the second week in veg. I am measuring how much less stretch that early preflower translates into.
 

wildgrow

, The Ghost of
Veteran
Well I decided to try the 14/1 I outlined above. My plants just seem ready and are starting to stretch regardless of the 18/6 I was just running. We will see. Whatever happens, will get documented here and in my thread. cheers
 

trichrider

Kiss My Ring
Veteran
12/1 initiated flowering on my favorite, so i aint using it anymore.

too bad too, i could use some relief (fiscal), that was the plan...back to 18/6.
 

blueberrydrumz

Active member
ICMag Donor
12/1 initiated flowering on my favorite, so i aint using it anymore.

too bad too, i could use some relief (fiscal), that was the plan...back to 18/6.
dont give up so quick, then why not try
12 on - 5 off - 2 on - 5 off
that should work...
all depends on whot you are trying to achieve...
peace
 

El Toker

Member
From what I've seen darkness affects the plant in three different ways.

The first is by initiating flowering, which takes a continuous dark period of up to 12 hours. (as short as 8 in one strain I've grown). You can't afford to mess around too much at this stage, although a 24 hour dark period right at the start of flowering does seem to give the process a little jump start.

The second is by keeping the plant in flower. During this stage you skip the odd dark period giving the plant a 12 hour photosynthesis bonus every three or four days and it does no harm, push it much further and you plant may become sexually confused.

The third is by determining the growth in length of the plant. I specify length because IME the total growth is pretty much directly proportional to the light period each day. A dark period will cause a plant to stretch itself but the total biomass would be less than if it had grown short and squat under 24/0 lighting. I've found 12 hours days of 6/6 to be useful for getting a mother plant to stretch to help me take cuttings without running the risk of sending it into flower. My guess is that you could probably get away with a 8 hour days 2/6 light cycle, but I've not tried that yet.
 

TLoft13

Member
12/1 initiated flowering on my favorite, so i aint using it anymore.

too bad too, i could use some relief (fiscal), that was the plan...back to 18/6.
As long as it isn't rare, why not replace the genetics? I'm recently converting to 12/1, and if some of my babies can't take it, tough luck for them.
 
12/1 initiated flowering on my favorite, so i aint using it anymore.

too bad too, i could use some relief (fiscal), that was the plan...back to 18/6.

just out of curiosity what genetics had problems? also were they new cuttings started under this lighting or were they under 18/6 for period of time prior to the switch of lighting?

Personally I wouldn't switch mother plants to this schedule that have grown under 18/6 for an extended period of time( more than a month), but starting new mother plants under that 12/1 should help as I have yet to have a plant switch into flower under 12/1.

So far:
Afgoo
GDP
Platinum Bubba
Black Domina
Sour Diesel
Northernberry

have all grown fine without incident, however I have yet to keep a plant in 12/1 for longer than 8 weeks as I only use it for filling up my screens for scrog under HPS before throwing them into flower. I continue to use 16/8 or 18/6 for mother plants depending on how much growth I need from them which are only under t-5s.

if that doesn't work for you there is always a little bit of saving using 16/8 for veg and 11/13 for flower which I found to be a good trade of yield and speed of flowering, but 12/1 has been even kinder on my pockets.
 

rangergord

Active member
I have been using these photoperiods for a few years now. Started with the infamous 12/12 from seed thread. On 12/12 the results are dependent on the strain to some degree. Sativas give the best results for sure. With 12-1 they do take a bit longer to veg but that is made up for by the shorter time to sex and less stretching as they go into flower. Also 12-1 works with those strains that do not care for 12/12 from seed.
I like saving electricity. Just bought a Canfan Max 6 and a 400 watt switchable dimmable lumatek eballast. This combined with a 12-13 hour light period is gonna save me power big time. Another option that I have tried is that I leave my HPS on 12/12 and then I add 6-12 hours of light with a CFL for a veg period when required. I use longer light periods for breeding autoflowering types. Otherwise you cannot be sure which plants are autoflowering when selecting progeny.
 

wildgrow

, The Ghost of
Veteran
I agree about not switching mothers that are accustomed to longer daylight.

M y own moms are still small so I think I can get away w/ it.

This thread should prove to be very interesting.
 

wildgrow

, The Ghost of
Veteran
After my 3/01 post, the preflowers from sexing had dried up. Now 4 days into the 14/1 cycle my plants have started a new round of preflowering. There arent more than before the change, so far so good. However, my mini moms (not all, just the skunk) have started flowering too. The minis are gonna be the ones I judge the outcome of this lighting change. I dont want to have to reveg them. Ill clone the hell outta them when I flip and just let the stumps ride out the 12/12. cheers
 

mr.brunch

Well-known member
Veteran
does anyone think there is any value to flowering at 13/11 (on/off)?
i do mine at 12.5/11.5 as i feel it keeps the temp / atmosphere in the room nicer somehow, and give more energy- does this make sense?
 
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