24-on 12-off light cycle

[GreenGrowth]

Hey all,

Has anyone heard of or tried the 24/12 light cycle during flowering?

I recently read an article about it and as interesting as it was, I am looking for results

 

[Stoned Ape]

I have wondered the same thing. Wasn't very sober at the time but. Just a stoner hunch but I think the plants probably want a 24 hr cycle.

 

[GreenGrowth]

I have wondered the same thing. Wasn't very sober at the time but. Just a stoner hunch but I think the plants probably want a 24 hr cycle.

Well if they only want a certain dark period, how do they know day length. The theory makes sense, that's why I'm looking for results

 

[Stoned Ape]

Someone out there knows this stuff. I m fried atm but I think it has something to do with the plant making and storing sugars/carbohydrates in the day and using it up in the night counting down the hours as it does it. That's the best my feeble mind can do right now

 

[Stormblessed]

Interesting concept, but I have no idea on if it would try to send ur plant back to veg every other day

 

[SmokingWings]

Hey all,

Has anyone heard of or tried the 24/12 light cycle during flowering?

I recently read an article about it and as interesting as it was, I am looking for results

It sounds interesting; if not to try at least to think about and maybe incorporate into our scheduling.

By any chance do you have a link to the article. If it was on another message board or someplace that would be against the rules then so be it. But, if it was a news story or a information article then those are usually acceptable. Or, do you remember where you saw it as in a hard copy printed marijuana magazine.

 

[SmokingWings]

Well if they only want a certain dark period, how do they know day length. The theory makes sense, that's why I'm looking for results

They don't know anything. They have no brain.

In order for the plant to go into a flowering mode it needs a period of darkness. Usually 12 hours are needed to start the production of the hormones that start the flowering. Most of the time 10 hours of darkness and the hour of dim weak light just after dawn and the hour just before sunset are enough to get the ball rolling. Then as the nights get longer more hormones are produced which is why I thing we notice that our outdoor plants have a spurt of flower growth come September (here in the US).

I have read message board threads where people have set their schedule to 15 or 16 hours of lights off and 9 or 8 hours of lights on..

People have had power outages with 24 to 48 hours of no lights before they can go back to their schedule, usually 12/12, and seem to have no problems.

Question becomes just how how long do the lights have to be on to allow for enough photosynthesis to replace sugars, etc that the plant has pulled up from what it has stored.

 

[GreenGrowth]

It sounds interesting; if not to try at least to think about and maybe incorporate into our scheduling.

By any chance do you have a link to the article. If it was on another message board or someplace that would be against the rules then so be it. But, if it was a news story or a information article then those are usually acceptable. Or, do you remember where you saw it as in a hard copy printed marijuana magazine.

Grow Faster With Long Light Cycles Written by Professor Lee

Indoor growers can speed up the flowering cycle of traditional and feminized strains of cannabis by simply changing the amount of light

www.weedworldmagazine.org

.

 

[SmokingWings]

Grow Faster With Long Light Cycles Written by Professor Lee

Indoor growers can speed up the flowering cycle of traditional and feminized strains of cannabis by simply changing the amount of light

www.weedworldmagazine.org

.

Thanks. I have the link and the web page and will read it later today or tomorrow.

Doesn't look like it is that long of an article so I will try to get to it sooner than later.

 

[CanadianJim]

There are some threads on here asking similar questions, including one guy who was going to try 18/12 and promised to get back to the forum with his results. Haven't seen anything about it since.
If you do decide to try this please keep us updated, let us know how it goes. It would be nice to have a final answer.

 

[SmokingWings]

I am not going to be trying this but it sounds like an interesting project for those who like to experiment.

The article does not get into why it works, just the claim that if the grower sticks with a light period of 24 hours and a dark period of 12 hours their plants will be ready to harvest sooner than if they had used the more traditional 12/12 schedule. The article then goes on to explain how to follow his suggestion of having the lights on for 24 hours and off for 12 hours using a 7 day programmable timer instead of the traditional 24 hour timer.

The 12 hour dark cycle works because the biologists have realized that the plant needs that much time to build up enough of the hormones needed to start and maintain flowering. The plant needs approx 12 hours of light for photosynthesis which provides the sugars, starches, etc needed for growth and maintenance. A certain amount of growth takes place during both the hours of light and dark.

While the author gets into how to program the timer to pull this schedule off he does not explain why the schedule works. He does not tell us just what is happening that the plant can finish the flowering cycle two weeks soon and do it without any loss in harvest weight.

A couple of starter articles that might help figure out what is happening during the extra hours of light and the regular 12 hours of no light. I have only done a quick read of them which is why they "might" help. The first one is very basic. The second link is to a sequence of short articles that are aimed at junior high to high school students (ages 12-17). The google search words were: do plants grow in the dark

Is a 24-Hour Light Schedule Bad for Plants?

Do Plants Grow Faster in Light or Dark?

Next up I will be looking through some of the articles in the search result page that appear to be linked to university web sites.

 

[Justin Goody]

I am not going to be trying this but it sounds like an interesting project for those who like to experiment.

The article does not get into why it works, just the claim that if the grower sticks with a light period of 24 hours and a dark period of 12 hours their plants will be ready to harvest sooner than if they had used the more traditional 12/12 schedule. The article then goes on to explain how to follow his suggestion of having the lights on for 24 hours and off for 12 hours using a 7 day programmable timer instead of the traditional 24 hour timer.

The 12 hour dark cycle works because the biologists have realized that the plant needs that much time to build up enough of the hormones needed to start and maintain flowering. The plant needs approx 12 hours of light for photosynthesis which provides the sugars, starches, etc needed for growth and maintenance. A certain amount of growth takes place during both the hours of light and dark.

While the author gets into how to program the timer to pull this schedule off he does not explain why the schedule works. He does not tell us just what is happening that the plant can finish the flowering cycle two weeks soon and do it without any loss in harvest weight.

A couple of starter articles that might help figure out what is happening during the extra hours of light and the regular 12 hours of no light. I have only done a quick read of them which is why they "might" help. The first one is very basic. The second link is to a sequence of short articles that are aimed at junior high to high school students (ages 12-17). The google search words were: do plants grow in the dark

Is a 24-Hour Light Schedule Bad for Plants?

Do Plants Grow Faster in Light or Dark?

Next up I will be looking through some of the articles in the search result page that appear to be linked to university web sites.

The plant will need more dark than light to flower. I’m currently doing 11 on/ 13 off with my only photo plant. If I put it to 24 on 12 off it is probably going to be confused and stay in veg forever. You’d likely have better luck trying 12 on 24 off.

 

[SmokingWings]

The plant will need more dark than light to flower. I’m currently doing 11 on/ 13 off with my only photo plant. If I put it to 24 on 12 off it is probably going to be confused and stay in veg forever. You’d likely have better luck trying 12 on 24 off.

It is the other guy's article. He does recommend starting the flowering by going with the standard 12/12 cycle. Then, once flowering has begun switching over to his 24 hours of light and 21 dark cycle.

The biggest problem with the article is that he does not explain why it works. He just says that the plants will be ready for harvest a couple of weeks sooner with no loss of weight. No mention of any increase in potency or even that the potency stays the same.

 

[Justin Goody]

It is the other guy's article. He does recommend starting the flowering by going with the standard 12/12 cycle. Then, once flowering has begun switching over to his 24 hours of light and 21 dark cycle.

The biggest problem with the article is that he does not explain why it works. He just says that the plants will be ready for harvest a couple of weeks sooner with no loss of weight. No mention of any increase in potency or even that the potency stays the same.

It’s an interesting concept, would love to see someone do an interesting experiment!

 

[Grandma Weedstein]

The plant will need more dark than light to flower. I’m currently doing 11 on/ 13 off with my only photo plant. If I put it to 24 on 12 off it is probably going to be confused and stay in veg forever. You’d likely have better luck trying 12 on 24 off.

The implication seems to be that plants aren’t necessarily beholden to the concept of 24 hour days, and will simply behave as if we’re on a different planet that somehow has 36 hour days. This parallel make-believe planet also slows its rotation every 24 hours and then doubles the speed for 12 hours. As long as a period of 12 hours of darkness is maintained, which is a signal for the plant to flower, presumably the longer period of daylight is irrelevant.

I’m not saying this is actually true, as this is the first I’ve heard of 24/12, but that’s how I understand the concept to work. Maybe it does, or maybe this is someone’s version of an elaborate prank aimed at getting you to fuck up your plants!

 

[SmokingWings]

It’s an interesting concept, would love to see someone do an interesting experiment!

Don't look for me to be that someone, at least not until someone else can explain just "why" it is supposed to be good for the final harvest.

Something else that just occurred to me is that the grower is going to have to plan ahead for the increase in temperatures in the grow area. I am thinking of all the members here who have mentioned problems with the heat in their grow room during the summer. 24 hours of non-stop lighting could raise the temperatures well into the 90s for some of us. And, if the plants go dormant during the periods of above 85 degree temps what is really being gained?

 

[SmokingWings]

The implication seems to be that plants aren’t necessarily beholden to the concept of 24 hour days, and will simply behave as if we’re on a different planet that somehow has 36 hour days. This parallel make-believe planet also slows its rotation every 24 hours and then doubles the speed for 12 hours. As long as a period of 12 hours of darkness is maintained, which is a signal for the plant to flower, presumably the longer period of daylight is irrelevant.

I’m not saying this is actually true, as this is the first I’ve heard of 24/12, but that’s how I understand the concept to work. Maybe it does, or maybe this is someone’s version of an elaborate prank aimed at getting you to fuck up your plants!

On a website that is supposedly pro-marijuana? The 12 hours of dark is needed for the hormone production and the longer period of light is irrelevant then why bother.

That is why I am stressing that there is missing information in that article, specifically, why it is beneficial to the plant to give it all that light.

 

[Grandma Weedstein]

I am not going to be trying this but it sounds like an interesting project for those who like to experiment.

The article does not get into why it works, just the claim that if the grower sticks with a light period of 24 hours and a dark period of 12 hours their plants will be ready to harvest sooner than if they had used the more traditional 12/12 schedule. The article then goes on to explain how to follow his suggestion of having the lights on for 24 hours and off for 12 hours using a 7 day programmable timer instead of the traditional 24 hour timer.

The 12 hour dark cycle works because the biologists have realized that the plant needs that much time to build up enough of the hormones needed to start and maintain flowering. The plant needs approx 12 hours of light for photosynthesis which provides the sugars, starches, etc needed for growth and maintenance. A certain amount of growth takes place during both the hours of light and dark.

While the author gets into how to program the timer to pull this schedule off he does not explain why the schedule works. He does not tell us just what is happening that the plant can finish the flowering cycle two weeks soon and do it without any loss in harvest weight.

A couple of starter articles that might help figure out what is happening during the extra hours of light and the regular 12 hours of no light. I have only done a quick read of them which is why they "might" help. The first one is very basic. The second link is to a sequence of short articles that are aimed at junior high to high school students (ages 12-17). The google search words were: do plants grow in the dark

Is a 24-Hour Light Schedule Bad for Plants?

Do Plants Grow Faster in Light or Dark?

Next up I will be looking through some of the articles in the search result page that appear to be linked to university web sites.

Unfortunately neither article deals directly with our question, which seems to be: Is cannabis flowering dependent on short days? Or is it dependent on long nights?

In other words, is it the number of daylight hours that’s important, or the hours of darkness? I’ve been under the impression it’s the hours of darkness, though I am not sure that the unusually long hours of light would not somehow “restart” the plant’s internal clock.

 

[Grandma Weedstein]

On a website that is supposedly pro-marijuana? The 12 hours of dark is needed for the hormone production and the longer period of light is irrelevant then why bother.

That is why I am stressing that there is missing information in that article, specifically, why it is beneficial to the plant to give it all that light.

I was joking about the elaborate prank but the implication is that the extra light hours will cause the plant to more actively produce flower during that time.

I have no idea whether that’s true, as you raise good points about heat and dormancy. I’d love to find out from someone with direct experience.

I’m not casting aspersions on this Weed World Magazine or Professor Lee, but I’ve never heard of either one. It’s certainly not a peer-reviewed study in an academic journal.

 

[SmokingWings]

Unfortunately neither article deals directly with our question, which seems to be: Is cannabis flowering dependent on short days? Or is it dependent on long nights?

In other words, is it the number of daylight hours that’s important, or the hours of darkness? I’ve been under the impression it’s the hours of darkness, though I am not sure that the unusually long hours of light would not somehow “restart” the plant’s internal clock.

I am with you on the hours of darkness. Everything I have read says that there is hormone production that takes place during the hours of darkness and low light that starts and maintains the growing of the flowers. If that period of hormone production gets interrupted for a long enough time then the plant stops producing the hormone and stops the flowering. End result is that the grower would have to give it another 12 hours of dark to start the process over again.