Reduced hour light cycles

potroastV2

potroastV2

Well-Known Member
Well, most of this thread is talking about light cycles for veg time. That makes little difference for the vegging plants.

For flowering, you want to give your plants light for as long as you can while still maintaining flowering. The 12 hours OFF is what makes them maintain flowering, but if you can maintain it while giving only 11 hours of darkness, you will get higher THC in your cannabinoid profile.


I know it was written over 30 years ago, and the research cited is older than that, I'm still going with Rob Clarke's Marijuana Botany. I give my flowering plants 13 hours of light and 11 hours of darkness.


Rob Clarke says that less than 12 hours of light per day will result in less THC produced. So here it is, like I've copied in threads on this board for years:


Marijuana Botany said:
"Research has shown (Valle et al. 1978 ) that twice as much THC is produced under a 12-hour photoperiod than under a 10-hour photoperiod."
(emphasis added)

So you can give your plants 10 hours of light per day, and they will produce half of the THC they would produce under 12 hours.

Therefore, I give my plants as much light as I can give them, while keeping them in flowering.

:mrgreen:
 
rkymtnman

rkymtnman

Well-Known Member
rollitup said:
If a flowering plant does not revert to vegetative growth, then it continues flowering. Some strains will continue flowering with only 10 hours of darkness.

:mrgreen:
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gotcha!
let's say that you try 11 OFF and it starts flowering. good so far. is it possible that at maybe week 6 it could revert back to veg? or once it starts flowering at 11, it will stay in flowering all the way to the end and you don't have to worry
 
torontoke

torontoke

Well-Known Member
rollitup said:
Well, most of this thread is talking about light cycles for veg time. That makes little difference for the vegging plants.

For flowering, you want to give your plants light for as long as you can while still maintaining flowering. The 12 hours OFF is what makes them maintain flowering, but if you can maintain it while giving only 11 hours of darkness, you will get higher THC in your cannabinoid profile.


I know it was written over 30 years ago, and the research cited is older than that, I'm still going with Rob Clarke's Marijuana Botany. I give my flowering plants 13 hours of light and 11 hours of darkness.


Rob Clarke says that less than 12 hours of light per day will result in less THC produced. So here it is, like I've copied in threads on this board for years:


Marijuana Botany said:
"Research has shown (Valle et al. 1978 ) that twice as much THC is produced under a 12-hour photoperiod than under a 10-hour photoperiod."
(emphasis added)

So you can give your plants 10 hours of light per day, and they will produce half of the THC they would produce under 12 hours.

Therefore, I give my plants as much light as I can give them, while keeping them in flowering.

:mrgreen:
Click to expand...
Well seeing as your a mod I will simply say I disagree strongly with the 30year old research.
I have grown a dozen different strains over the last few years using only 8hrs to flower and if I'm missing half the thc then I think I'd have noticed.
I am legally allowed to purchase from government producers, dispensarys and my own has smashed it so either I'd be the greatest 12/12 grower ever or this is yet another example of old research being proven wrong.
I'm leaning to the latter but then again as always I will take the high road and simply say we can all agree to disagree.
 
potroastV2

potroastV2

Well-Known Member
rkymtnman said:
gotcha!
let's say that you try 11 OFF and it starts flowering. good so far. is it possible that at maybe week 6 it could revert back to veg? or once it starts flowering at 11, it will stay in flowering all the way to the end and you don't have to worry
Click to expand...
That's not entirely correct. Once a plant is flowering, it can be reverted to vegetative growth at any time. Some growers induce their plant to flowering to determine sex, and then increase the light hours to cause them to purposely revert to veg growth so she will continue to grow and get bigger before flowering again.

You can tell when a plant is reverting because the foliage will change, from mature leaves back to single leaflet leaves, then grow some 3-leaflet leaves, and so on. A plant can take a month or more to revert fully and continue vegging. It is typically not worth the time and effort.

When we control the photo period, we can make the plant do whatever we wish. :bigjoint:

:mrgreen:
 
potroastV2

potroastV2

Well-Known Member
torontoke said:
And how many have u tried
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How many have I tried? I don't know what you are asking. If you want my history, I started growing pot in the early '70s, and have grown over 100 crops. I set up my first Hydro garden in '78 when virtually no one even knew what Hydro was. I've been helping other growers for 20 years.

If you are talking about how many crops flowering using less than 12 hours of light, of course I've never done it, because of what I just posted about here. I read Dr. Clarke's book 30 years ago, so naturally I would not waste a crop by doing that. Like I said, I want my plants to be the best that I can make them perform. Why would I want to produce bud that is less than optimal cannabinoid profile?

I'll leave stuff like that to the newbie growers. :lol:

:mrgreen:
 
torontoke

torontoke

Well-Known Member
rollitup said:
How many have I tried? I don't know what you are asking. If you want my history, I started growing pot in the early '70s, and have grown over 100 crops. I set up my first Hydro garden in '78 when virtually no one even knew what Hydro was. I've been helping other growers for 20 years.

If you are talking about how many crops flowering using less than 12 hours of light, of course I've never done it, because of what I just posted about here. I read Dr. Clarke's book 30 years ago, so naturally I would not waste a crop by doing that. Like I said, I want my plants to be the best that I can make them perform. Why would I want to produce bud that is less than optimal cannabinoid profile?

I'll leave stuff like that to the newbie growers. :lol:

:mrgreen:
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Yes I just started.
Total newb clearly
Your years of experience with growing using a completely different method is not at all what I was asking.
My humble experience has shown different results then what your research has told you but tbh I am not trying to sell anything nor do I recommend how anyone else grows.
I think everyone is entitled to an opinion and I'm not arguing this topic any longer.
 
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WeedSexWeightsShakes

WeedSexWeightsShakes

Well-Known Member
rollitup said:
How many have I tried? I don't know what you are asking. If you want my history, I started growing pot in the early '70s, and have grown over 100 crops. I set up my first Hydro garden in '78 when virtually no one even knew what Hydro was. I've been helping other growers for 20 years.

If you are talking about how many crops flowering using less than 12 hours of light, of course I've never done it, because of what I just posted about here. I read Dr. Clarke's book 30 years ago, so naturally I would not waste a crop by doing that. Like I said, I want my plants to be the best that I can make them perform. Why would I want to produce bud that is less than optimal cannabinoid profile?

I'll leave stuff like that to the newbie growers. :lol:

:mrgreen:
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Ever thought research from 30 years ago could be wrong? Sorry but the way you communicate isn’t like a mod. Making immature comments at torantoke isn’t proving anything. Just my opinion tho.
bongsmilie
 
potroastV2

potroastV2

Well-Known Member
Well, some of you guys have your "opinions," and you think it's "logical" to do what you do. :roll:

I guess that's the only way you can justify ignoring research. After all, gravity is just a theory, right?

:mrgreen:
 
C

churchhaze

Well-Known Member
It doesn't take a research paper to see that 11 hours of light will have a lower DLI than 13 hours of light. How do plants yield more mass with less energy? Why not cut off some fan leaves to speed up flowering?

I still think the recent RIU trend is backwards and that 13/11 will yield more.
 
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C

churchhaze

Well-Known Member
Cannabis doesn't transition into the stretch. The stretch is the transition itself and the response happens IMMEDIATELY after switching the light period.

The stretch response is part of the veg cycle! When the plants are fully switched into flowering mode, they will not respond to the shade avoidance effect anymore.
 
stnr420

stnr420

Well-Known Member
torontoke said:
Over the last yr or so I keep reading more n more posts about people trying alternative light cycles in their rooms and rather then having the results and info scattered I thought why not start a thread.

So if your running a schedule other then 18/6 to veg or 12/12 to flower please feel free to post your results and experiences.

If you haven't tried anything then please skip to the next hps is better than led thread and argue there Instead.
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I run 18/6 under fluorescent for 2-3 weeks..then under mh i run 16/8 for 2-3 weeks...then the week b4 flip 14/10....then at flip i run 11/13 all the way till the last week then 10/14....works great and saves energy...also i think it may reduce stretch and allow a faster finish...
 
ttystikk

ttystikk

Well-Known Member
stnr420 said:
I run 18/6 under fluorescent for 2-3 weeks..then under mh i run 16/8 for 2-3 weeks...then the week b4 flip 14/10....then at flip i run 11/13 all the way till the last week then 10/14....works great and saves energy...also i think it may reduce stretch and allow a faster finish...
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A lot of people say that GLT (gaslight timing) accelerates the transition into bloom. 12 hours on, 5.5 hours off, 1 hour on, 5.5 off and repeat.

Have you tried anything like this?
 
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