24 hour Dark Period before Harvest ? ?

Bearbudzz

Bearbudzz

Connoisseurous Cannabis
I tried searching the title on here but came up with zero.
Has this subject been tossed about on the island ?
I have a friend that insists that leaving your plants in the dark for 24 hours before harvesting will activate more THC. . :hmm:
The interweb chatter is all over the board.
My feelings are that the cream hangs out here and will have the answer ! . :adore:
:pl:
 
I`ve done it several times just to see . Up to 72 hours of dark . I`ve seen no noticable difference in trichs or taste .
peace
 
And what about the other, 24 -48 hour of hanging in the dark after chop, to kill chlorophyll, does that change anything much?
 
burnie said:
I`ve done it several times just to see . Up to 72 hours of dark . I`ve seen no noticable difference in trichs or taste .
peace
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Same here, tried lots of dark time schemes before harvest, no diff.

Dark for extra 24 hr before flip may coax preflowers if they haven't shown.
 
Hashmasta-Kut said:
And what about the other, 24 -48 hour of hanging in the dark after chop, to kill chlorophyll, does that change anything much?
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I always hang in the dark. Bright lights isn't good for the herb but I doubt if normal room light would be a problem for the 5-10 days drying.
 
I think the reasoning for this comes from the growing and harvesting of culinary herbs. Herbs, like thyme/rosemary/sage all derive their smells and flavors from terpenes, like cannabis. During the day with herbs, sunlight and temperature will increase the rate that terpenes are being lost to the air, this effect is absent during the night. If you are observant, you might notice that growing herbs smell and taste the strongest at the end of the night, before sunrise, due to the fact that the accumulation of terpenes isn't being removed by the aforementioned process. Same with cannabis, I notice that my room has the most stink just before lights come on, and smells the faintest prior to lights off.

That's just what I think anyway, and I do try to harvest either just before lights on or after a 24 hour dark period.
 
I have used this technique for years. I put the plants in total darkness for 48 hrs before harvest. And they are never exposed to anything but green light until gone.

I have gotten to the point that sometimes I do it and sometimes I don't. Honestly I don't really notice any difference. Anymore I do it because I want to get the nest generation into flower.
 
I do the 24 or 36 hours of darkness every time, depending on if it's a night time run or a daytime, we trim during the day and it's a wet trim, I think it makes the weed smell stronger.... not sure about anything else, but you know when the light first comes on Terpenes are supposedly at their highest...
 
hela said:
That's just what I think anyway, and I do try to harvest either just before lights on .....
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:hmm:
So from this I take it that when you harvest you chop all your plants at one time ??

I have always harvested one plant at a time.Starting at the top and working my way down,trimming and hanging as I go. .
:puffpuffpass:
 
I never noticed any difference. I highly doubt it would increase any cannabanoids full percentage points and even if it raised THC say .03 or even .3 would we even really notice?
 
hela said:
If you are observant, you might notice that growing herbs smell and taste the strongest at the end of the night, before sunrise, due to the fact that the accumulation of terpenes isn't being removed by the aforementioned process. Same with cannabis, I notice that my room has the most stink just before lights come on, and smells the faintest prior to lights off.

That's just what I think anyway, and I do try to harvest either just before lights on or after a 24 hour dark period.
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My friend had an outdoor plant this years that backs that up; He had a very skunky plant this year outside, and every morning he said it reeked intensely, but by afternoon the odor was pretty much nonexistent. He was really surprised; it was a big difference.
 
A few friends and myself all used light dep at the end of harvest, for a few years. Seems the concept was to reduce chlorophyll production and allow maturation of the flowers. Personally, the best flowers I've ever grown to this day were subjected to light dep at the end of harvest. I can't remember how long that was, probably 3 or 4 days or something like that. I did have to water them in the dark. Room was cool, probably 6o degrees F. Low speed exhaust fan on the ceiling. I can't say for sure that light dep is what made that harvest great, but it was a factor that time around.

I eventually stopped doing this because of the extended time factor. Seems I can get the same quality by harvesting on time, drying and curing properly.

edit: I'm reminded of something I heard or read somewhere.. about 'your grandmas tomatoes' and how she would drape a white bed sheet overtop of the tomato plants before harvesting to improve the flavor. The concept of light dep seems to be very old, but so far grower testimony alone is all we have to go on.
 
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Bearbudzz said:
:hmm:
So from this I take it that when you harvest you chop all your plants at one time ??

I have always harvested one plant at a time.Starting at the top and working my way down,trimming and hanging as I go. .
:puffpuffpass:
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Bear, when i started being dillagent about chopping just minutes before lights come up i started harvesting by tops. Chop the whole table at once. I found it makes for a better cure as well because all tops are drying at the same rate and can be treated as a group during drying to more precisely control moisture at given points (i buck first, then hang, then break down mains onto net stackers, then turkey bag) Sometimes ill let the lowers keep growing to fully ripen like we do outdoors.

I agree with hela, def notice that indoors and out....i love that morning plant smell.

Seems somewhat logical that terpenes may be produced in the dark, and if so perhaps for more than 12 or 24 hours? Although at some point growth will be confused by unnatural darkness and diminishing returns...

Perhaps the best solution to diminish potency loss would be to actually switch from HIDs to normal lights on the same schedule, during the period immediately prior to starting the curing process (1-5 days?), in order to maximize final flower aroma?
 
I am still toying with this idea, but with the LED tower as the light source I have not had vigorous growth like with HID, but they grow and stink. My first run of Pineapple Jack was very pineapple taste and scent at first, that changed a little.
This 2nd run is Hash Berry and just harvested her last night, again some very strong smelling aroma, so sweet and berry at this point
I think proper spectrum LED's help promote more flavornoids, as I turned off all white and blue LED's and just let the others on for last few days.
If what I have read is true the key is near 360nm UVA rays that help most.

Dark period, yes there is a little something to it, but not over 48 hours of darkness, after that point one does more harm than good, so I read.
Top shelf genetics it does not matter, lower shelf genetics it does make a difference that a smoker can notice. longer deeper flavor, that how I remember it.:puffpuffpass:
 
I am skeptical that any treatment for 24-48 hours would have an appreciable effect on THC levels. I do recall reading a study years ago that THC levels were highest right before dawn, but I highly doubt it would be something that was noticeable.
 
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