Flowering with anything other than 12/12. Does it work/help?

eyderbuddy

Well-Known Member
All of these count:
  • 10/14
  • 6/6
  • 11/13 or 13/11
  • 730nm pucks
  • far red (any other kind)?
  • intermitent?
Is there really any benefit to this other than some arbitrary/personal need?

I'm interested in the subject but i've no space to try it out atm. I've heard anywhere from faster flowering times (claims include: 1 week faster to 4 weeks faster), bigger yields, smaller yields, more frost, more stretch, ya dada da da da...

Also, i've read the Cannabis Sativa characterization study and they tried with 11/13 and got smaller yields. 13/11 Gave them bigger yields but wasn't worth the increased power consumption. Which sounds like they didn't control for their photon count (mol/day) so that may explain their findings..

Seeing as the vast majority just follow the 12/12 rule, can those who differ chime in at all?
 
heard of 10 hours of light per day before. the only problem in my mind is that it give the plant less energy per day and as a result would give less energy for bud growth. It does save energy so that's a benefit I guess.
I also put the plant in a 2 day dark period before harvest. I have been told this reduces the chlorophyll in the plant, there by minimizing the planty taste for those whom are inpatient and can't be bothered to cure properly.
 

Thundercat

Well-Known Member
There are definite differences to the light cycles. 12/12 is the most common, but many growers use or at least experiment with different times. I believe you actually only need about 10 hours of darkness to get the plants to flower typically, however, 12 hours allows the transition to happen faster due to the flowering hormones building up faster.

I've read many times about growers using going with different times ranging between 10-14 hours of darkness. From my understanding, different cycles will usually cause changes in phenotypical expression in the plants. I read an interview with the breeder DJ Short years ago where he stated that he has found a non-12/12 cycle to me optimum, however, he didn't say what he actually used. If I remember correctly he stated that his cycle ended on a half hour.....
 
I thought the light destroyed the hormone that induced flowering. If that was true then 10 on and 14 off would allow for more of this hormone, not 12/12.
Also now that im thinking I remember a grow where i had a defective outlet. It made my led panel turn off and on randomly sometimes even flickering. When i was in there it would go on and off pretty rapidly until i discovered it and fixed it. Actually I thought it was the extension cord at first so It went longer until realized the real problem. I wonder if a 10 minute on and 10 minute off would speed things up. The plants in question were clones in a cloner and they all started shooting pistols before I corrected the problem. Wasted a lot of time getting it back into veg, dam outlet! It was a lesson to be learnt, check your plants daily.
 

Beachwalker

Well-Known Member
I thought the light destroyed the hormone that induced flowering. If that was true then 10 on and 14 off would allow for more of this hormone, not 12/12.
Also now that im thinking I remember a grow where i had a defective outlet. It made my led panel turn off and on randomly sometimes even flickering. When i was in there it would go on and off pretty rapidly until i discovered it and fixed it. Actually I thought it was the extension cord at first so It went longer until realized the real problem. I wonder if a 10 minute on and 10 minute off would speed things up. The plants in question were clones in a cloner and they all started shooting pistols before I corrected the problem. Wasted a lot of time getting it back into veg, dam outlet! It was a lesson to be learnt, check your plants daily.
Let us know if that works, because if it does we'll take it one step further and use strobe lights, they should speed it up even more
 

Thundercat

Well-Known Member
I thought the light destroyed the hormone that induced flowering. If that was true then 10 on and 14 off would allow for more of this hormone, not 12/12.
Also now that im thinking I remember a grow where i had a defective outlet. It made my led panel turn off and on randomly sometimes even flickering. When i was in there it would go on and off pretty rapidly until i discovered it and fixed it. Actually I thought it was the extension cord at first so It went longer until realized the real problem. I wonder if a 10 minute on and 10 minute off would speed things up. The plants in question were clones in a cloner and they all started shooting pistols before I corrected the problem. Wasted a lot of time getting it back into veg, dam outlet! It was a lesson to be learnt, check your plants daily.
Yes 10 on 14 off would increase the flowering hormone, making flowering happen even faster. 10 on doesn't give tons of hours of light for them to grow as well though. Its all a balancing act.
 

eyderbuddy

Well-Known Member
heard of 10 hours of light per day before. the only problem in my mind is that it give the plant less energy per day and as a result would give less energy for bud growth. It does save energy so that's a benefit I guess.
I also put the plant in a 2 day dark period before harvest. I have been told this reduces the chlorophyll in the plant, there by minimizing the planty taste for those whom are inpatient and can't be bothered to cure properly.
Yes 10 on 14 off would increase the flowering hormone, making flowering happen even faster. 10 on doesn't give tons of hours of light for them to grow as well though. Its all a balancing act.
What if we increase PPFD to match the lost hours?

Make it so the plants get the same amount of light per day regardless of the hours? Of course there would be a limit to this as eventually it'd just be too much light too quick... Any thoughts?

11/13 works for me, good luck !
Any difference from 12/12 at all?
 

CoB_nUt

Well-Known Member
10/14 for for years now.
Less power consumption.
Some strains finish faster(In my setup)than they did when ran 12/12.
Once your plant reaches it dli limit,more light saturation is moot.IMO & IME.
Transition to flower is shorter.<too many other variables to list that may contribute..
Temp are more stable which I attribute to less heat. I veg and flower in the same room.
These are just some of the benefits I have found the 2 hour difference has made.

No reduction in yeilds,taste,budsize(unless I fuck up ) or potentcy.
 
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eyderbuddy

Well-Known Member
So i did some more reading and found some interesting stuff in a 2009 study:

THE PROPAGATION, CHARACTERISATION AND
OPTIMISATION OF CANNABIS SATIVA L
AS A PHYTOPHARMACEUTICAL

5.5.4.3 Review of the comparisons of plants induced to flower on daylengths 11, 12 and 13 hours.

Amongst the major findings, from the studies comparing the effect of daylength, it was found that increasing the daylength from twelve to thirteen hours increased energy consumption by at least 8%, but resulted in no beneficial increase in botanical raw material yield. There was sometimes also an unwelcome increase on plant height. Effects of increased day length on cannabinoid yield were variable, with some clones showing a large decrease in cannabinoid production at the longer day length. Conversely, reducing the day length to eleven hours saved energy by approximately 8% but resulted in an economically unacceptable and statistically significant 15 – 20% mean reduction in plant yield (p < 0.01). There was also a significant reduction in the mean cannabinoid yield (p < 0.01 after 10 wks in short days).


So a lower day length basically reduced yields by weight and by cannabinoid count... But it did improve how "finished" the were.

5.5.4.2 Comparison of Eleven and Twelve Hour Daylength Regimes

Whereas reducing the day-length from thirteen to twelve hours had a dramatic effect on floral development, a further reduction to eleven hours only marginally accelerated the cessation of new flower formation, Table 5.10.
Plants in 13h days continued to make new flowers way past the point of harvest, on the other hand plants in 11h days ceased making new buds and focused on "ripening". By the 10th week the 11h plants had more "finished" buds than the 13h plants. This also resulted in relatively lower cannabinoid yields for the 13h plants, mainly because of the fresh new growth. All of this supports the whole "longer nights make them finish faster" but with reduced yields. But also opens the doors for being "inducing a finish" for the 12-14 week sativa strains after enough bud has been produced.

It's also important to notice how strain dependent this this. Some strains had a very significant yield increase from the 13h days, while only 1 had a yield reduction.



I assume that more equatorial strains would benefit even more from longer days during flowering, in order to increase yields and later a 2 week 11h period to induce the finish.
 
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eyderbuddy

Well-Known Member
I think my next experiment will be trying 1 plant with 12/12 and another with 10/14 but with the same daily light integral values (~40mol)...

Since none of the studies i've read on the subject have controlled for this variable
 

Moldy

Well-Known Member
All of these count:
  • 10/14
  • 6/6
  • 11/13 or 13/11
  • 730nm pucks
  • far red (any other kind)?
  • intermitent?
Is there really any benefit to this other than some arbitrary/personal need?

I'm interested in the subject but i've no space to try it out atm. I've heard anywhere from faster flowering times (claims include: 1 week faster to 4 weeks faster), bigger yields, smaller yields, more frost, more stretch, ya dada da da da...

Also, i've read the Cannabis Sativa characterization study and they tried with 11/13 and got smaller yields. 13/11 Gave them bigger yields but wasn't worth the increased power consumption. Which sounds like they didn't control for their photon count (mol/day) so that may explain their findings..

Seeing as the vast majority just follow the 12/12 rule, can those who differ chime in at all?
Clark says 12/12 is best. Just repeating what was written in his book.

https://www.amazon.com/Marijuana-Botany-Advanced-Propagation-Distinctive/dp/091417178X
 

old buzzard

Well-Known Member
I was going to try on my current grow,,when there is about a week to go taking 15 minutes of light off each end and go 11 1/2-12 1/2. and drop temperatures at night a couple degrees.Not based on anything other than curiosity.In nature each day we get less light until harvest.Just curious to see what if any thing changes.I think there will some type of reaction.Cannot see where it will hurt anything.I know the strain will make the biggest difference if results are positive or not.Barneys-Ayahuasca Purple and canuk seeds-Kushy Kush.the kushy kush is my wife's and friends favorite if I screw it up I will hear about it.LOL
 

xtsho

Well-Known Member
My timer has been on 10/14 for a couple of grows now. I messed up when I set it awhile back and didn't want to change it to 12/12 in the middle of flower. I forgot again when I started my next crop in the flower tent. Everything seems to be doing just fine. They might be somewhat smaller but I'm not sure. Without doing a side by side I don't know. Your mind will play tricks on you so if you think there might be a negative effect then you could very well think there is even when there isn't.
 

old buzzard

Well-Known Member
My timer has been on 10/14 for a couple of grows now. I messed up when I set it awhile back and didn't want to change it to 12/12 in the middle of flower. I forgot again when I started my next crop in the flower tent. Everything seems to be doing just fine. They might be somewhat smaller but I'm not sure. Without doing a side by side I don't know. Your mind will play tricks on you so if you think there might be a negative effect then you could very well think there is even when there isn't.
when you compare the 10/14 with the 12/12 grows you have done.were any of them the same strain.reason I ask is just curious if everything else was same if there was a difference in smell,taste,even small things you noticed.Not talking bud size, buds are always big enough for me.everything we smoke now is half breeds I find it interesting to see different traits come out that may, by manipulating light time.There have been noticeable differences I seen before I had the environmental control I have now.Might get extra hot or cold and seen how that has effected things.But never talked to someone who has worked with light time and personally seen the results.Just curious good day
 

torontoke

Well-Known Member
I was going to try on my current grow,,when there is about a week to go taking 15 minutes of light off each end and go 11 1/2-12 1/2. and drop temperatures at night a couple degrees.Not based on anything other than curiosity.In nature each day we get less light until harvest.Just curious to see what if any thing changes.I think there will some type of reaction.Cannot see where it will hurt anything.I know the strain will make the biggest difference if results are positive or not.Barneys-Ayahuasca Purple and canuk seeds-Kushy Kush.the kushy kush is my wife's and friends favorite if I screw it up I will hear about it.LOL
You won’t notice any difference in such a minor reduction in light on hours.
It’s not a significant enough change to cause any reduction in flower time or negative effects imo.
As for your second question the difference between a 10hour and 12 hour cycle are a few days shaved off the total days and no loss of yield or thc percentage.
There’s plenty of people on this forum alone running 10/14 now and if even one of them noticed a significant change I doubt they would still be doing it.
 

Dr. Who

Well-Known Member
Clark says 12/12 is best. Just repeating what was written in his book.

https://www.amazon.com/Marijuana-Botany-Advanced-Propagation-Distinctive/dp/091417178X
Books say lots of things...

Real world work in your environment will always be different then his environment.

I prefer 11/13 with most strains.
Longer running Sativa's start at 12/12 and along the way. Begin to get lowered. OR, get dropped (in lighting times) if they seem to get stuck or lag at finishing properly.

In running 11/13. I find a more "stable" bloom running plant. This is why I choose to run it...
 

xtsho

Well-Known Member
when you compare the 10/14 with the 12/12 grows you have done.were any of them the same strain.reason I ask is just curious if everything else was same if there was a difference in smell,taste,even small things you noticed.Not talking bud size, buds are always big enough for me.everything we smoke now is half breeds I find it interesting to see different traits come out that may, by manipulating light time.There have been noticeable differences I seen before I had the environmental control I have now.Might get extra hot or cold and seen how that has effected things.But never talked to someone who has worked with light time and personally seen the results.Just curious good day

Now that I think about it I have flowered Pakistani Chitral Kush at 12/12 and 10/14. I didn't notice any difference and if there was it was minor and not noticeable.
 
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