6/12 light cycle

I am reading the book Marijuana Horticulture Fundamentals by Ken Morrow aka K.

It suggests using a weekly timer to run 6 on 12 off in flower to conserve 30% electricity.

Has anyone here actually tried this and care to share your experience please? As a relative newb whose done much research Im apprehensive to try without having heard from a few of you who can get behind it.

I’m almost ready to flip my new room to flower....

You must mean 12 on and 24 off. Plants won't flower with 24 hours of light unless you're growing auto's.

I've never done it and never will.

Sorry I meant 6 on 12 off.

sounds like you are the canary in the coal mine.

start a journal!!

Somebody did this a few years ago and it was not good. I'll see if I can dig up who it was.
If you have intense light, perhaps try 9 on, 12 off. But 6 just won't be enough.

Hot Diggity Sog said:

Somebody did this a few years ago and it was not good. I'll see if I can dig up who it was.
If you have intense light, perhaps try 9 on, 12 off. But 6 just won't be enough.

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torontoke i think?

rkymtnman said:

torontoke i think?

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Yes, that is him. 2015/2016 time frame I believe.

If your worried about electric you should have got smaller lights. you can go like 11 on 13 off but anything less is not advised.

I am not concerned about the electric bill much.

It sounds like a bad idea in my mind, particularly given your guy's feedback.

If the plant gets 30% less light/energy I wouldn't be surprised if it is 30% smaller than normal. Ever action has a reaction.

I'm finding this book to be just so-so... It seems there are very few high quality and modern up-to-date books on cannabis horticulture. Jorge Cervantes, Ed Rosenthal.... good but slightly dated. "K"? Not sure... the chapter on lighting said to go and read Jorge's book which didn't even mention LEDs and is 10-15 years OLDER.

Maybe I am learning a few things from this book by K, but some if it is questionable or very particular and peculiar, perhaps even half baked, with holes in it.

Throw the book away

are you sure it's not for veg, gas lamping? 5.5off 1 on 5.5 off dark period / 12hr on light period , then just switch to 12/12

Forgot where this was talked about, maybe ICMag. It was 6/12 for a smaller, faster harvest. And 24/12 for a bigger, slower harvest

Here is the big thread from @torontoke

He did a lot of work on irregular flowering light cycles and sub 24 hour days. I followed along for a while until it became clear that you just can't flower effectively with only 6 hours of light per day. He started his work using 6 on/18 off.

Again, you can run 11/13. Otherwise if your worried about power, get smaller lights or spend the big bucks on high end LED but keep in mind you will need to get your canopy temps around 80-85 which can be hard to do with LED.

The light schedule I use, which does save electricity, and DOES work for most plants is:

Veg -- 12 on, 5.5 off, 1 on, 5.5 off
Flower -- 8 on, 16 off

It sounds crazy but it ends up making the plants less strung out on light. They don't need 18+ hrs in order to veg. They just need an interrupted dark schedule to prevent them from creating the hormones that send them into flower.

On the flower side, 8 hours is plenty. I've proven this to myself with the last 2 grows I've completed since I switched. Both indica and sativa hybrids doing fine with no apparent difference in yields.

The one exception is my OG Tahoe mother that I've been running for years and which I got from other growers who ran for years at 18/6 or 24 for veg. It likes to put out lots of trichomes and early pistils in veg, but it doesn't get to full flower until you put it into 8/16. It looks weird having a trichome covered mother plant but you can still clone it just fine and it never goes to full bud.

I did have one very strange plant called Elephant that I popped a seed and it started growing buds under the veg regime but I'm not entirely sure about that strain anyway. Everything else goes great so far.

If you do the math, that is 28% less electricity than 18/6 for veg, and 34% less than 12/12 for flower.


I learned all this from Joe Pietri but I don't recommend anyone go joining his fan club because he's pretty much a dick, and his seeds are way overpriced. He does have a good thing going with the light schedules though.

At the risk of giving this guy too much spotlight, I'll drop the link because he does have a lot of good information.

http://www.growlikejoe.com/growing/
http://www.growlikejoe.com/growing/tips/

Thsnks for sharing your experience. So what is the advantage? You just save money on electric?

Or anything else? Pls unpack "Not so strung out on lignt" as if it actually helps? Or just saves money?

Overgrowtho said:

Thsnks for sharing your experience. So what is the advantage? You just save money on electric?

Or anything else? Pls unpack "Not so strung out on lignt" as if it actually helps? Or just saves money?

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You'll have to visit the link I posted. It's basically this:

Cannabis can only uptake 8 hours of light energy for photosynthesis, its tanks are full.

When you give it more light energy, the plant goes into photosynthesis protection, which use up energy and shuts down CO2 intake.

So now you are using the energy received to its utmost potential, no energy wasted, no CO2 shutdown, the plant now has 16 hours to grow fatter buds and produce more resin than ever before. 8 on 16 off in flower is the game changer.

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and this:

Why does your plant stretch?

You created a light junkie on 18-6, 20-4, 24 on, in veg. When you switch to 12-12, the plant stretches for a light fix.

All of those schedules make no horticultural sense.

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GrownAtHighAltitude said:

You'll have to visit the link I posted. It's basically this:




and this:

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"Light Junky" lol. mmmmkayyy.....

JoeBlow5823 said:

"Light Junky" lol. mmmmkayyy.....

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