48 - 72 hours of darkness before harvest

[Admiral Canna]

IMO it is a total wate of time to do any darkness peroid for the end of flowering prior to chop.

Trichomes have several functions.....protection from insects/predators (smell/sticky), protection from UVB light, protect pistils to better chances of pollination, protect seeds for best chance of survival for next generation.......I know I'm missing one or two more.....

but IMO, dark periods at the end have no purpose at all. Tried it, won't do it again.

 

[inphu510n]

Thanks for the info guys. I had no idea.
So much hype about different methods of whacking the plants.

 

[DirtySouthTo707]

Think that may be a little early to stop feeding IMHO. I also give nuttn but sweet and molasses in the end at about 6-7 wks. And plain ro after that.

 

[Herbal extasy]

Tried it in last grow, didn't notice a shit.

 

[HansHanf]

tried it 2 times vs. 2 times w/o the 3 days of darkness...
no difference between...

 

[bigwity]

i heard if you add uv light for 30 mins a day in the last few weeks it increases trichs but ive not tried it. im also glad to read this thread so take no notice of him

 

[eastbaybeast]

I have done it both ways and I prefer to keep the lights on 'em up until harvest.

Couldn't see any more trichs with more darkness. All it did was made them lose the rest of their fan leaves quickly. If you need this, then go for it.

 

[Kush_Master]

what if you turn off the lights for 48-72 hours in week 8 when they still have 2 weeks to go?
does that influence the plants negatively?

 

[kp^]

I don't think some people understand when and why you give your cannabis a darkness period before the chop. It seems people are ignorant about the process and saying things like "well the plant could just use 3 more days of light...." Well if your plant is DONE, and READY to chop, why he F would you give it 3 more days?

There is a process to harvest, and if it is not done right then your meds may not turn out as expected.... or taste like shit because you didn't flush.. lots of variables...

I belive there was a thread on this SAME subject not to long ago.... I could not find it, so I'll post the info again.....

I've been putting my crops into a 24-48 darkness before I ever read any books. I saw the results with my own eyes. Within the last year I did pick up Jorge Cervantes Marijuana Horticulture and medical growers bible... Jorge did mention putting your plants into a darkness which does help resin production.

Basically, when you think your crop is done...(looking at trichs) You put yer ladies in a 24-48 hours of darkness (3days does nothing more IMO). When you place your plants into the dark you should already be flushing for the prior week. Basically the darkness tricks your plant into thinking its dying, thus there is an increase in resin production.

From my experience some strains will benefit more than others, but I will always continue to place my plants into a 24-48 darkness before I chop them...

Happy Growing!

 

[Kush_Master]

what if you turn off the lights for 48-72 hours in week 8 when they still have 2 weeks to go?
does that influence the plants negatively?

since im leaving for a festival tomorrow and would like to turn off the lights in that time i would really appreciate a quick answer!

 

[asstastic]

sorry for not finding the thread but one of the seed banks did a test and plants given 24-48h darkness showed a 3% increse in thc compared to those left in light for the same time
ask dutchgrown she's who i heard it from

 

[staff11]

3% lol, not really worth waiting for to be honest.

 

[bigwity]

yeah your right not worth it......................lol why bother.

id hate my plants to be as potent as possible. especially if i have to wait 2 more days lol

 

[unta]

^yeah for sure, i mean higher potency would be horrible.

 

[staff11]

Like you will even notice a 3% increase, but whatever to each their own. This kind of stuff reminds me of people putting nails through stems, hanging upside down to increase potency, all BS myths really. I wont waste my time when they are done they are done, darkness or not.

I have Cervates book to, and the guy while a very experienced grower makes contradicting remarks ALL throughout the latest version.

In his harvest section at step three he says quote:

"You may want to give the plant 24 hours of darkness before harvest.Many growers do this and say the buds are a little resinous afterward."

And just because someone doesn't agree with a technique, it does not mean they are ignorant.....
No where in that statement does he say he actually does this and again it looks like just total speculation to me.

 

[mafia]

Considering a strain with 20% thc is a pretty good amount, I would say a 3% increase would be noticable.

 

[chits]

Like you will even notice a 3% increase, but whatever to each their own. This kind of stuff reminds me of people putting nails through stems, hanging upside down to increase potency, all BS myths really. I wont waste my time when they are done they are done, darkness or not.

Haha,, I still do.
Pull it up, roots and all.
Rinse the roots, wrap loosely in sheet / cheese cloth, and snap off while getting brittle moving closer to buds as it dries.
Hanging in a cool cellar, fair air flow, moderate humidity it seems to give a nice slow cure. Definately takes more than a week or two though.
Seems to bring out the flavor, improves the smoke and burn.
Being in a damp local, this may not work so good in Arizona or Panama.

3%? Worth a few days to me..... anytime.

I wonder if my old 60's style is like the darkness thing? (probably)

 

[staff11]

The plant isn't increasing in 3% potency, just because it has 3% extra Trichomes doesn't mean it is 3% stronger. Been plenty of plants grown with less then optimal amounts of frost that are just as potent. It's not always an indicator...... If you want to use this technique, go for it. I still say it doesn't do a damn thing.....

 

[floral]

I had been reading and researching and trying to find the definitive answer to whether darkness makes a difference, and finally remembered that a friend of mine is a botanist. Asked her about starches in the plants at daytime vs. night time and in a matter of hours she sent me a scientific article about starches and plants' circadian rhythms. Now I just have to understand what it says LOL. Posted with PDF in the Botany and Advanced Growing Science forum (in main forum menu, one level up from Growers' Forum).

Key paragraph:

An important hallmark of the circadian clock is its free-running 24-h rhythm. Free running refers to the fact that, once entrained by light signals, the circadian clock maintains a 24- h rhythm in continuous light or continuous darkness, anticipating dusk and dawn according to previously encountered conditions. In fact, the property of being a 24-h timer has revealed the involvement of the circadian clock in the control of starch degradation. When plants are grown in light–dark cycles shorter or longer than 24 h, abnormal starch degradation patterns are observed during the night. In 28-h light–dark cycles (14 h of light, 14 h of darkness), starch is degraded extremely fast, so reserves are exhausted before dawn—specifically, at 10 h into the night rather than at the actual dawn after 14 h of night (Fig. 1b). Conversely, in 20-h light–dark cycles (10 h of light, 10 h of darkness), starch is degraded too slowly, resulting in the presence of substantial reserves at dawn. If the night is extended beyond dawn, starch is eventually depleted after approximately 14 h of darkness (Fig. 1c).

Not a scientist but if this applies to our gardens it seems like harvesting after a darkness is beneficial, but super-long dark periods aren't any better than shorter ones. Also seems like a steady photoperiod is crucial so the plants can time their transport activities.

 

[floral]

circadian rhythm and starch reserves

circadian rhythm and starch reserves

I had been reading and researching and trying to find the definitive answer to whether darkness makes a difference, and finally remembered that a friend of mine is a botanist. Asked her about starches in the plants at daytime vs. night time and in a matter of hours she sent me a scientific article about starches and plants' circadian rhythms. Now I just have to understand what it says LOL. Posted with PDF in the Botany and Advanced Growing Science forum (in main forum menu, one level up from Growers' Forum).

Key paragraph:

An important hallmark of the circadian clock is its free-running 24-h rhythm. Free running refers to the fact that, once entrained by light signals, the circadian clock maintains a 24- h rhythm in continuous light or continuous darkness, anticipating dusk and dawn according to previously encountered conditions. In fact, the property of being a 24-h timer has revealed the involvement of the circadian clock in the control of starch degradation. When plants are grown in light–dark cycles shorter or longer than 24 h, abnormal starch degradation patterns are observed during the night. In 28-h light–dark cycles (14 h of light, 14 h of darkness), starch is degraded extremely fast, so reserves are exhausted before dawn—specifically, at 10 h into the night rather than at the actual dawn after 14 h of night (Fig. 1b). Conversely, in 20-h light–dark cycles (10 h of light, 10 h of darkness), starch is degraded too slowly, resulting in the presence of substantial reserves at dawn. If the night is extended beyond dawn, starch is eventually depleted after approximately 14 h of darkness (Fig. 1c).

Not a scientist but if this applies to our gardens it seems like harvesting after a darkness is beneficial, but super-long dark periods aren't any better than shorter ones. Also seems like a steady photoperiod is crucial so the plants can time their transport activities.