Dark period before harvest – how long?

RockoCalenberg
RockoCalenbergstarted grow question 3mo ago
Dark period before harvest – how long? Do you chop with no change in light cycle, or give 12h, 24h or 48h darkness before harvest? And when do you cut: morning before lights on, daytime or night? Curious what works best in your experience. Grow on đŸŒ± Rocko
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Week 19
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HandsomeTerpz
HandsomeTerpzanswered grow question 3mo ago
In my experience the long dark period before harvest is one of those topics where growers have many opinions, but the actual effect is often smaller than people expect. I have tried several approaches over the years. I tested harvesting with no change to the light cycle, giving the plants about 24 hours of darkness, and once even close to 48 hours. What I personally observed was that the difference in potency or aroma was not dramatic. The plants that had a short dark phase before harvest sometimes seemed a little more aromatic when trimming, but the final dried product was very similar. Because of that I usually keep things simple now. I let the plants finish their normal flowering schedule and then harvest shortly before the lights would normally turn on. The idea behind that timing is that during the dark phase the plant has already slowed down metabolic activity and resin production has stabilized. Many growers believe terpene levels are slightly better preserved at that moment. If someone wants to add a dark period, around 24 hours is a reasonable choice. It gives the plant time to finish moving some stored energy and can slightly increase resin expression on some cultivars. Going much longer than that usually does not provide clear benefits in my opinion and sometimes just stresses the plant unnecessarily. The most important factor is really harvesting at the correct ripeness. Watching the trichomes and the balance between cloudy and amber heads makes a much bigger difference to quality than the length of the final dark period. So my routine is fairly straightforward. Normal flowering cycle until the plant is ready, lights off as usual, and then harvest in the early morning before the lights come back on. Simple, consistent, and it has produced very good results for me. Happy Growing and Enjoy 😊
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JVKdopegrow
JVKdopegrowanswered grow question 3mo ago
Beautiful work! I cut early after an overnight dark, but that is convenient for me as much as any other reason.
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JUNGLE_B4RNS
JUNGLE_B4RNSanswered grow question 3mo ago
Harvest a few hours before lights turns off, Before the sugars that have been photosynthesized, during the light period, sinks to the roots to feed the bacteria when lights goes off. Sugars moves from SOURCES to SINKS. This is called the Pressure Flow Hypothesis. Buds are one of the sugars sources. This is one of the technics used to make candy buds with a high sugar content tasting very sweet. (PS: Source for the binary garden dwarf) Georgia Institute of Technology : https://organismalbio.biosci.gatech.edu/nutrition-transport-and-homeostasis/plant-transport-processes-ii/
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Ultraviolet
Ultravioletanswered grow question 3mo ago
Majority of terps and trichs are processed at night when the plants oxidative capacity is free and available to work. Mornings are always the best time for any harvest because of this. No if ands or buts. Dark period is a point of contention and is grossly misunserstood in its purpose. 48-72 hours of complete darkness is a biological signal trigger that initiates a response from the plant that potentially increases the release of enzymes that assist in the accelerated degradation of chlorophyll right before harvest. Essentially initiating "PCD" Programmed cell death. How much it helps? Is arbitrary, in my opinion every 0.25% is worth it. On that note I wouldn't worry about it. Plant autophagy is a well-documented, conserved, and essential component of plant biology, functioning as a major intracellular degradation and recycling system that maintains cellular homeostasis. But grandmaster guru cannabis cultivators call it BS without a 2nd thought. Whether people want to misconstrue its use is entirely up to them. Ignorance is bliss. Rather than do darkness do excess "blue light" for last week of ripening, replacing full spectrum with 5k+. This gives her a little boost. Signals increase in smellies. Works well from my experience. Best o luck those trichs look amazing 👏. Don't need anyone's advice!
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Nocone_Purple
Nocone_Purpleanswered grow question 3mo ago
In my experience the dark period before harvest doesn’t make a big difference. Some growers give 24–48h darkness, but there’s no strong evidence it increases potency or terpenes. I usually keep the normal light cycle and harvest right before lights would turn on, since terpene levels are often highest then.
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Organoman
Organomananswered grow question 3mo ago
Extended darkness is BS. Chop about one hour after lights on and with a normal light cycle. Works for me for decades already. A plant in darkness can not function. A plant that is not functioning can not support health. There is no magical way to alter anything in a few hours that has taken weeks to develop. Have done many, many experiments over the years and like I said, extended darkness is BS imo............just like the supposed benefits of molasses.
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squalino
squalinoanswered grow question 3mo ago
salut ,C'est une question qui divise Ă©normĂ©ment la communautĂ© des cultivateurs ! Cette technique, souvent appelĂ©e la "pĂ©riode d'obscuritĂ© prĂ©-rĂ©colte" (gĂ©nĂ©ralement de 48 Ă  72 heures), repose sur quelques thĂ©ories mais n'est pas une obligation absolue. ​Voici un rĂ©sumĂ© pour t'aider Ă  dĂ©cider : ​Pourquoi certains le font ? (Les avantages thĂ©oriques) ​L'idĂ©e est de stresser la plante une derniĂšre fois pour "booster" sa production finale : ​Production de rĂ©sine : On pense que la plante, se sentant mourir, produit un dernier pic de trichomes et de rĂ©sine pour protĂ©ger ses graines (mĂȘme s'il n'y en a pas). ​PrĂ©servation des terpĂšnes : Les terpĂšnes (qui donnent l'odeur et le goĂ»t) sont volatiles et se dĂ©gradent Ă  la lumiĂšre et Ă  la chaleur. L'obscuritĂ© totale et une tempĂ©rature plus fraĂźche aideraient Ă  les conserver au maximum juste avant la coupe. ​DĂ©gradation de l'amidon : Sans lumiĂšre, la plante consomme ses rĂ©serves de sucres et d'amidon, ce qui rendrait la fumĂ©e plus douce et moins "verte" en bouche. ​Pourquoi d'autres ne le font pas ? (La rĂ©alitĂ©) ​Risque de moisissures : C'est le danger principal. Si ton taux d'humiditĂ© est Ă©levĂ© (au-dessus de 50-55%) et qu'il n'y a pas de lumiĂšre pour chauffer l'air, l'humiditĂ© peut stagner dans les tĂȘtes denses et provoquer de la pourriture (botrytis). ​Preuves scientifiques limitĂ©es : Il n'y a pas d'Ă©tudes dĂ©finitives prouvant que 48h de noir changent radicalement le taux de THC. Beaucoup de cultivateurs pro prĂ©fĂšrent simplement couper la plante Ă  l'aube, au moment oĂč la concentration de terpĂšnes est la plus haute. ​Mon conseil "sĂ©curitĂ©" ​Si tu dĂ©cides de le faire : ​VĂ©rifie l'humiditĂ© : Garde une extraction d'air active et assure-toi que l'air circule bien. ​DurĂ©e : Ne dĂ©passe pas 48 heures. Au-delĂ , le risque de moisissure l'emporte sur les bĂ©nĂ©fices. ​L'alternative : Si tu as peur de la moisissure, contente-toi de couper ta plante juste avant que la lampe ne s'allume (ou au lever du soleil). C'est le moment oĂč la plante est la plus "chargĂ©e" en bonnes choses. ​Note importante : N'oublie pas que le plus important pour la qualitĂ© finale reste le rinçage (arroser Ă  l'eau claire les 10-14 derniers jours) et surtout un sĂ©chage len
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00110001001001111O
00110001001001111Oanswered grow question 3mo ago
Doesn't have a measurable effect, and any negative effect will be imperceivable. Do whatever floats your boat. Can't argue with magic. I've read you should harvest before lights come on, but not sure if that was based on anything real or just more anecdote. Years ago i would turn off the light timer the night before a harvest, but nowadays i grow 8 plants at a time and not going to interrupt the dark cycle of the other plants. Years of doing both and i cannot tell a difference. So, even if there is a measurable statstically significant effect, It must be incredibly small and irrelevant. Just because soemthing has a measurable effect or correlation doesn't mean human senses can notice a difference or that the effect is profound and worthwhile to be of concern. That's a seperate question for each context you look at. For example, blue and red wavelengths have measurable and real effects on plant morphology that i will never debate, but it will never turn a short, squat plant into a stretched out plant, for example. Half my room is 2900K half is 3400k and again... relative to genetic diversity it is impossible to recognize the difference they have on plant morphology. i could assume things, but I have short plants under the red-heavy light and i have lanky plants under the blue-heavy light -- it's signifcantly more about genetics than the CCT of the light above them. Maybe, if i did a room full of clones i'd notice 'something,' but it'd still be a small effect. Use such things to your advantage when possible, but of little concern if you cannot. I.E. If i could see the future, i'd put the short plants on the red side and the tall plants on the blue side, but ... I do not have powers of foresight, lol. Once they grow through the scrog, which has a profoundly more beneficial effect, the plants don't move around.
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KuaerSchlaeger
KuaerSchlaegeranswered grow question 3mo ago
You don't need to go through the 48 hours of darkness; it's pointless. Harvest before the lights come on.
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Mooncat
Mooncatanswered grow question 3mo ago
You could do the opposite and go for 48 Hours of light like Prof. Bugbee suggested. That might do something. The effects will be negligible in any case ether way.
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ATLien415
ATLien415answered grow question 3mo ago
the only trick here is to harvest in the dark period, with any changes to the natural rhythm you have already set the leading weeks being meaningless to the plant. this is, in fact, known if i took you said now you work 3rd shift instead of 1st shift, you will take days to weeks to acclimate on a physiological level...she is the same. you can see this based on EC metrics over time in hydro solutions at night relative to day; for the same reason you harvest when the most free salts have been exchanged downward into root mass. roughly 3 hours into dark until roughly 3 hours before light is your sweet spot, trading salt uptake into the plant mass from roots increasing for nominal trichome repair increase... both of these are things that are on 24 hour time cycles anyway... doing for example 48 hours of random darkness for the plant at the end of an established photoperiod has been categorically shown to be a nothing-burger. watching EC over time shows that the plant still behaves (for days to weeks later) as if the original schedule was true still
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GoodWeedBerlin
GoodWeedBerlinanswered grow question 3mo ago
I had times doing the dark-period-before-harvest-time, but I chose science over bro-science. And science can sometimes be very easy: Without light a plant can not doing photosynthesis. With the motor off, you do not get any benefits from/for your plant. Or at least not more benefits than from harvesting before the light go on in your usual light-schedule. To harvest before lights go on is very common among growers cause a part of the terps get lost the longer the day.
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HinduGod
HinduGodanswered grow question 3mo ago
I AM NOT DAT PICKY!!! MOST TIMES I CHOP WHEN ITS CONVENIENT FOR DA HINDUGOD!!!! 85% OF DA TIME DAT IS JUST BEFORE DA LIGHTS TURN ON!!!!
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Green_Claws
Green_Clawsanswered grow question 3mo ago
I like to give 48 hrs dark.. This can't be proven, some would say it's broscience I say 🖕
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Growfather1
Growfather1answered grow question 3mo ago
I chop them down after 24 hours of darkness some go for 4 days. I tried 4 days ending up with dry stems and partially dried buds, I didn't water the plant so the roots pulled al the moisture from the plant. So if you go for longer than 24 hours keep watching for dry soil. You did a good job there Rocks cheers.
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