14 hours of darkness have you tried this???

motoxmom

Active Member
so i just read this and was wondering how many people have tried this? this is from ed rosenthal
Marijuana is a short-day plant. As the days get shorter, marijuana determines when to flower based on the number of hours it receives of uninterrupted darkness. It measures the length of the dark period using the hormone phytochrome, which has two states. The hormone’s inactive state, Pfr, occurs when it absorbs red spectrum of light at 666 nanometers. It also has a slight sensitivity to blue light. The hormone changes to its active form, Pr, over a period of two hours when the plant is in darkness. When the Pr flowering hormone levels remain high for a critical period of time over several days, the plant changes from vegetative growth and initiates flowering.
The number hours of darkness plants need to initiate flowering differs by variety. Sativas require a longer period of darkness than indicas because they developed near the equator, where the length of daylight is much more consistent than at northern latitudes, where indicas developed. Some sativas continue to grow vegetatively with 10 or 11 hours of darkness, which usually cues most plants to flower.
Many sativas initiate flowering only when the dark cycle increases to 12 hours or more, which occurs September 22 in the Northern Hemisphere.
By contrast, most indicas flower with 8 to 11 hours of uninterrupted darkness (13 to 15 hours of light). In southern tiers of Europe and the U.S., a few indica varieties flower as early as June 22, the shortest night of the year. For this reason, outdoor gardeners in these regions should consider sativa-indica hybrids and sativas. In the central and northern tiers, indica and indica-sativa hybrids usually start flowering in August and are ready to harvest in September through mid-October.
Some sativas and sativa hybrids require a longer dark period at the end of flowering to fully ripen their buds. Outdoors, this happens in due course as the nights lengthen in the fall. Indoors, change the lighting regime to 14 hours of darkness/10 hours of light to promote ripening. This is especially helpful in finishing low latitude varieties that don’t reach maturity in their native lands, where there is no winter, until the middle of the short-day season.
 

chis

Active Member
i put them in tottal darkness for the last 24 to 36 hours it seems to work my trics look alittle bit fuller. i am just not convenced but i have done it only twice still working on it.
 

Chem Dawg

New Member
I am currently experimenting with 11/13. Haven't noticed much of a diff yet. But it's only been about 3 weeks.
 

GrowersBook.com

New Member
I am currently experimenting with 11/13. Haven't noticed much of a diff yet. But it's only been about 3 weeks.
I was going to start testing that as well when I flip in a week. Would love to hear updates on your progress with this method.

Based on the info from Ed at the top, it seems to me that this would probably work better with Indicas and Hybrids than it would with pure Sativa's. But only one way to find out for sure!
 

motoxmom

Active Member
well here is my update but idk if it was the buds or the light switch but my trichs changed to mostly amber on the bbk from yester 50% and the bd has some amber now when none yesterday (i am checking same buds same places) and the pp well it has 50 amber now so its definatly changed but was it to soon???? check out my journal for updates :)
 

motoxmom

Active Member
ok so day 2 of 10/14 and hairs are mostly all red now and receded into buds, trichs still same as yesterday. anyone else ever try this?
 

cowell

Well-Known Member
I do this too.. 10/14 for the last 3 weeks... It will speed up the finish on your plants by about a week.
My nugs were big and tight.. different style of growing, but I am sold that it makes a difference. I also do 48 hours dark before harvest. This is only because light degrades THC. If you have no light degrading the THC already in the trichs.. the plant will continue cranking THC out until it recognizes that it doesn't need ot put out as much.. MJ usually can adapt to things very fast.. 3 days is about all it takes. I'm at week 6 of flower on Wed.
 

motoxmom

Active Member
awesome, i did it my 1st time didnt the 2nd and now am trying it again on my 3rd grow. it is so cool to see someone else has tried this. i did think i saw a difference in density and trichs. but wasnt to sure. and i wanna try the 48hrs but i have 4 different grow times. maybe next time :)




I do this too.. 10/14 for the last 3 weeks... It will speed up the finish on your plants by about a week.
My nugs were big and tight.. different style of growing, but I am sold that it makes a difference. I also do 48 hours dark before harvest. This is only because light degrades THC. If you have no light degrading the THC already in the trichs.. the plant will continue cranking THC out until it recognizes that it doesn't need ot put out as much.. MJ usually can adapt to things very fast.. 3 days is about all it takes. I'm at week 6 of flower on Wed.
 

cowell

Well-Known Member
awesome, i did it my 1st time didnt the 2nd and now am trying it again on my 3rd grow. it is so cool to see someone else has tried this. i did think i saw a difference in density and trichs. but wasnt to sure. and i wanna try the 48hrs but i have 4 different grow times. maybe next time :)
Why not just pull one plant out of your room- unless stink is a concern... Then you can compare and see what difference a dark period makes for your particular strain and environment. You may not be able to, but if can get away with it, you won't be sorry you tried it, much like the 10/14 at the end of your cycle. Anyway, good luck- I'll pop my head in and see how things finish up for you ;)
 

Illegal Smile

Well-Known Member
Is everyone growing sative and no indica? The most interesting part of this is that Indicas should need only 8-10 hrs of darkness which means they can have 14-16 hrs of light out of 24. That's more energy which should translate into more growth and more yield.

This would seem to me (if you find it credible) to be a good reason for switching from sativa to indica.
 

cowell

Well-Known Member
violator kush - indica
strawberry cough - indica dominant
kandy kush - indica.

The reason for the reduced light time at the end of the cycle is to force the plant to finish early. It's photosensitive - obviously.. so you reduce the light hours and it will hurry up and mature based on the fact it will think it's at the end of it's life cycle based on the hours.
Longer light periods - on paper - should equal more growth as far as I think too, but, I've only done it once, so I can't "swear" on a stack of bibles that I'm positive it works 100% of the time.. but I noticed my buds were bigger, and definately frostier than last grow. that I finished out at 12/12. Worth looking into though.
 

Illegal Smile

Well-Known Member
My understanding is that the plants need x (whatever that is) hrs of dark to begin flowering and continue to flower. I haven't been persuaded that "extra" dark has anything to do with when a plant "finishes" which to us means is ready for harvest. I'm not sure why a plant would be in a hurry to do that, I think it's just our hurry. Maybe I'm wrong.
 

cowell

Well-Known Member
If I'm not mistaken - don't you also subscribe to the "plants need sleep" argument too?
I'm not looking to pursuade anyone. Like I said, I did it once so far, made a difference in my honest opinion, so I'm doin it again to see how they look this time around. You think it won't do anything...so you won't try it. Whatever. I tried it saw good results first hand. I don't need to understand the physics behind flight to know planes fly - I see them all the time.
You don't understand the effect of light deprivation on a c3 plant. I seem to be a little more up on that research.
 

Illegal Smile

Well-Known Member
If I'm not mistaken - don't you also subscribe to the "plants need sleep" argument too?
I'm not looking to pursuade anyone. Like I said, I did it once so far, made a difference in my honest opinion, so I'm doin it again to see how they look this time around. You think it won't do anything...so you won't try it. Whatever. I tried it saw good results first hand. I don't need to understand the physics behind flight to know planes fly - I see them all the time.
You don't understand the effect of light deprivation on a c3 plant. I seem to be a little more up on that research.
Defensive much?

No I don't subscribe to plants need sleep, so you're mistaken on that, too. I veg 24 hrs and do autos 24 hrs. If my plants want more than 12 hrs of dark somebody will have to convince me it has merit. Maybe I don't "understand" the effect of light deprivation. I'm sure I'm not alone in that. Maybe someone will come along who has some scientific knowledge instead of just anecdotal beliefs.
 
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