experienced growers only...

pAn1c420

Member
this question is to all EXPERIENCED growers...Does giving the plants 48 to 72 hours of darkness to a plant before harvest really make a difference? to people that have tryed it before...
 

researchkitty

Well-Known Member
Sometimes it takes me that long to cut a harvest, and there's never any difference other than its harder to trim because its not as wet from drying out. ;-)
 

rzza

Well-Known Member
heres the thing, you will see results but they are the same reults you would see if you kept them on 12/12 for the same 48 to 72 hours. i have done this but again the results are not tremendous trichs like people say it is. the plant is throwing trichs on like crazy the last few days and weeks. if your wanting the extra resinous buds IMO just leave em a couple days after you decide to chop. FWIW i did 48 hours darkness and cold.
 

pAn1c420

Member
i still goin to wait til 4/11 than cut them down so i can at least smoke a dried bud by 4/20 than the rest is getting cured...
 

skunkushybrid01

Well-Known Member
plants need light to grow... hormones.

cytokinin equals cell division, auxin equals cell elongation.

ATP is energy... energy is created from light. In the dark, energy only lasts so long... plant will preserve energy i theorise, thus producing less buddage and trich's and potency.

IMO
 

pAn1c420

Member
ok let me rephrase the question...Does giving the plant 48 to 72 hours of darkness before u cut it down make a difference???
 

brainfreezer187

Active Member
There are many threads on this... Also with that said there are many opinions on the subject. personally i have done with 12/12 all the way and 48 hour darkness its no big difference just turn it off last 2 days and save your electric
 

J.W.

Well-Known Member
There are many threads on this... Also with that said there are many opinions on the subject. personally i have done with 12/12 all the way and 48 hour darkness its no big difference just turn it off last 2 days and save your electric
I have found that 36 hours of total darkness does seem to give me more resinous buds than 12/12 the last couple days. I used a 60X pocket microscope to make comparisons. When a plant gets close to harvest and is not yet pollinated, it will naturally start to produce more resins as the pistils draw in and it gets closer to the end of the reproductive cycle. Plants produce most resin during the dark cycle, so the reasoning is that the last 36 hours -- or at least 24 hours, the plant should be given total darkness, and about 25% of the existent resin will turn amber while another small percentage is produced. Again, we're not talking the difference between dirt weed and dank here, but I did feel like the buds were greasier and displayed more resin compared to the same plants that got 12/12. Just don't do it too early OR go any longer than 36 hours, or you risk popping some nanners and it herming out last minute. Some experienced breeders actually do this to study and master self-pollination.
 

EFILROFKGD

Active Member
although my post count does not reflect my experience i can assure u that 2-3 days darkness does not do much for the plant.. its what u do the first 60 plus days that matter
 

garlictrain

Well-Known Member
for fine tuning an already awesome grow i would say it makes a huge difference!

after 48hrs darkness my plants were "wet" to the touch with resin! usually use gloves anyway, but after this dark period there was an all encompassing sheen of resin over everything the bud contacted. this from the same genetics i've used for 3+ yrs under 4k.

as it was explained to me by a vet organic grower, resin production is used partly as a block from uv rays. uv rays gradually degrade surface resin, when the lights go off the resin production peaks to restore its uv blocking layer.

also from personal experience:
when using genetics with different finishing times i will put entire room in 48hrs darkness at end of wk 9. wow this really peaks resin!
after i pull all varieties done at wk 9 i shorten the photo period to 6/18, leaving the remaining sativa dom varieties until wk 12.
using this method i have successfully finished (amber trichs) 14wk thai dom sativas in 12 wks!

from the vet organic grower: he says that using this 6/12 method as a breeder works great. when working with strains known for sensitivity (most landrace thai), it allows one to remove genetic characteristics of intersex plants.

will be using this technique again on upcoming harvest!
 

J.W.

Well-Known Member
I'm sure you're familiar with TGA's breeder, Subcool, and here's what he had to say on another forum I'm a member of about giving a dark period before harvest, particularly a 36 hour dark period:

People ask me why I place my plants in the dark for a few days before harvesting and there are two answers.
The first was coined by a good friend of mine and I have never heard it stated better:

The flower/bloom cycle of cannabis is controlled by a chemical/hormone that builds up during dark hours, so during veg with only 6 hours dark, the plant doesnt build up enough of this hormone to trigger flowering responce... once dark hours are lengthenned then slightly more hormine is produced during 12hrs dark than is destroyed during 12 hours light... so after roughly 2 weeks the hormone builds up to a level that triggers the flowering stage..

So... near the end of the plants life you can force the plant to produce every last bit of resin possible by tricking the plant by extending the dark cycles, in effect you are giving the plant 3 nights worth of dark in 1 blast which allows the hormone to build up to maximum levels, pushing the plant to finish quicker and produce as much thc as possible.. and ripen thc it has already produced...

Pistils...


The other reason is if I remove the plant from the bud area It either makes more room for other plants to receive better light OR it makes room for another plant to start budding.

Sub
 
This sounds interesting and sounds like it might work so when it comes time on my current grow I think I will give it a try. Should I leave my pumps running and continue to water during this time or should I stop watering them. I usually do not water during dark hours but it might help with the final flush
 

pAn1c420

Member
J.W thanks for the info...i think i'm goin to try out...and i don't know if this make since but i kinda believe wat u said cuz for some reason every morining the room i have them in stinks so good...
 

J.W.

Well-Known Member
This sounds interesting and sounds like it might work so when it comes time on my current grow I think I will give it a try. Should I leave my pumps running and continue to water during this time or should I stop watering them. I usually do not water during dark hours but it might help with the final flush
I would most definitely NOT water during this dark period. Your humidity would sky rocket, and your nearly-finished buds are susceptible enough to bud mold without this added risk. Also, you should be letting your plants dry out almost to the point of wilting before harvest anyway, so it's easier to manicure the buds and they won't taste green and full of chlorophyll, AND they'll dry and cure a little better and faster. This is good advice, trust me.
J.W thanks for the info...i think i'm goin to try out...and i don't know if this make since but i kinda believe wat u said cuz for some reason every morining the room i have them in stinks so good...
No problem. I thought I noticed a difference, and when I saw what Subcool had to say, I felt a little better myself. Besides, even if it doesn't make a difference, as long as you don't overdo it, it certainly doesn't hurt!

J Dub
 

skunkushybrid01

Well-Known Member
although my post count does not reflect my experience i can assure u that 2-3 days darkness does not do much for the plant.. its what u do the first 60 plus days that matter
well said.

although it has been proven that stress will increase potency, it is a waste of energy to induce that stress using extensive dark hours.

Indeed, you might as well slap the plant around a little, give it a good shake, bang a nail in the middle of the stem. All stress, and the plant will respond by producing more trich's... and more potent trich's too. It's a scientific fact.

One of the best things you can do is to trim the plant while it is still flowering. Trim off all the big leaves for the final week of flower... plants can still photosynthesise using the little leaves. During the final week the plant will frost right up.

I wouldn't bother myself of course, i already grow dank... no need to fix what isn't broke.
 

macrael

Well-Known Member
wow thanks for helpful tips guys as i am coming up on my last week of flower from Monday. is my first one also but if it works for you guys there s no harm in it for me!!!
just to be clear on the subject 36h of darkness is sufficient and i have to water every two days so i am guessing to stop watering aleast a the day before i go in 36 hours of dark nights.
 

probo24

Well-Known Member
this question is to all EXPERIENCED growers...Does giving the plants 48 to 72 hours of darkness to a plant before harvest really make a difference? to people that have tryed it before...
Yes it makes a difference.
How much of a difference,
well that depends.
My answer is as vague as your question.
 

J.W.

Well-Known Member
well said.

although it has been proven that stress will increase potency, it is a waste of energy to induce that stress using extensive dark hours.

Indeed, you might as well slap the plant around a little, give it a good shake, bang a nail in the middle of the stem. All stress, and the plant will respond by producing more trich's... and more potent trich's too. It's a scientific fact.

One of the best things you can do is to trim the plant while it is still flowering. Trim off all the big leaves for the final week of flower... plants can still photosynthesise using the little leaves. During the final week the plant will frost right up.

I wouldn't bother myself of course, i already grow dank... no need to fix what isn't broke.
I agree with most of what you said. . . except the waste of energy part. On the contrary, to NOT give a dark period would be a waste of energy. If you concede the fact that it does indeed produce trichs to give a dark period, then why would you "waste the energy" of leaving the lights on for the last two days? Besides, this dark period is nowhere near as stressful as HST or physically harming the plant. Those actually release different hormones. Trimming the plant slightly the last week or so also does help, I agree.
 

skunkushybrid01

Well-Known Member
I agree with most of what you said. . . except the waste of energy part. On the contrary, to NOT give a dark period would be a waste of energy. If you concede the fact that it does indeed produce trichs to give a dark period, then why would you "waste the energy" of leaving the lights on for the last two days? Besides, this dark period is nowhere near as stressful as HST or physically harming the plant. Those actually release different hormones. Trimming the plant slightly the last week or so also does help, I agree.

Do you know what ATP is?

Do you know when ATP is created?

It is only created during photosynthesis... without ATP the plant cannot produce sufficient buddage. Once the lights go down the plant needs to conserve what ATP it has made into surviving till the lights come back on and more ATP can be manufactured. So how does the lights going down save energy? they don't, the plant is constantly losing it. Only when the lights are on can the plant build sufficient energy to last it through any dark period.

It's the light period that releases different hormones. During lights on, cytokinins are more active, lights out auxins are more active. Cell division and cell elongation, respectively.
 
Top