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Dark period before harvesting.... Is it a myth?

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KD
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Dark period before harvesting.... Is it a myth?

Post by KD »

The Theories


There's a few theories about the best way to harvest your buds, including keeping them in up to 72 hours of darkness before the actual chop. But is it all nonsense?

Image

Thrichomes containing THC, among all the other cannabinoids, are believed to be produced as the plants way to protect itself from the effects of harmful UV radiation from the sun and other mildly stressful environmental factors. Suddenly turning off the sun for a few days is said to increase THC due to a stress response.

Another theory is that it evolved from the plants need to pollinate before winter. As the nights grow shorter, the plants produce more and more trichome covered buds in the hope of being pollinated and producing seeds. This doesn't make sense as no one can switch off the sun for days at a time in order for this evolution to happen.

Finally, the theory that makes most sense to me, is that cannabinoid levels fluctuate over 24 hours. They peak just at the end of the dark period and are degraded during the day as they protect the plant from UV radiation. During the night, the plants replenish the degraded trichomes ready for the next day. By extending the dark period, the plants should be producing more cannabinoids than normal.

The Science


I can't actually find the scientific papers that prove any theory but the story goes that there were experiments carried out by the Stichting Institute of Medical Marijuana (SIMM). In the experiment they harvested half of their plants as normal, and kept the other half in darkness for 72 hours. When they later analyzed the final crop, the THC level in some of the strains was up as much as 30% compared to the buds harvested normally.

The same is also true for Terpines. During the day, these evaporate and are replenished during the night cycle. These are what make your plants smell amazing and also add to the entourage effect. After 48 hours in darkness, your plants REALLY begin to smell, and this is why.

How long is enough?


If you're in a rush, the best time to harvest is right before the lights are due to come on. This ensures no cannabinoids have been degraded yet.

You'll barely notice any difference after 24 hours darkness either as the process has only just started to elevate but you can do it for 48 - 72 hours and get good results. Some people claim they've done it for up to a week before, but I haven't tried this at all.

Just remember that the longer you leave it... The less solid your buds become.

Mould & Bud Rot


If you're going to try this... Make sure you don't water your plants so the soil or coco is dry before you do. Lower humidity = more THC and high levels of moisture in the air or ground can lead to Mould and the dreaded bud rot!

Discussion


Have you tried this? Do you swear by it? What were your results? I do it every time although I don't remember if it does make things better, it just makes a lot of sense to me to do it this way.
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Growmie (Mon Nov 15, 2021 11:40 am) • duke (Thu Nov 18, 2021 4:37 pm) • biosynthetic (Fri Nov 19, 2021 3:17 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by duke »

KD wrote:
Mon Nov 15, 2021 10:22 am
The Theories


There's a few theories about the best way to harvest your buds, including keeping them in up to 72 hours of darkness before the actual chop. But is it all nonsense?

Image

Thrichomes containing THC, among all the other cannabinoids, are believed to be produced as the plants way to protect itself from the effects of harmful UV radiation from the sun and other mildly stressful environmental factors. Suddenly turning off the sun for a few days is said to increase THC due to a stress response.

Another theory is that it evolved from the plants need to pollinate before winter. As the nights grow shorter, the plants produce more and more trichome covered buds in the hope of being pollinated and producing seeds. This doesn't make sense as no one can switch off the sun for days at a time in order for this evolution to happen.

Finally, the theory that makes most sense to me, is that cannabinoid levels fluctuate over 24 hours. They peak just at the end of the dark period and are degraded during the day as they protect the plant from UV radiation. During the night, the plants replenish the degraded trichomes ready for the next day. By extending the dark period, the plants should be producing more cannabinoids than normal.

The Science


I can't actually find the scientific papers that prove any theory but the story goes that there were experiments carried out by the Stichting Institute of Medical Marijuana (SIMM). In the experiment they harvested half of their plants as normal, and kept the other half in darkness for 72 hours. When they later analyzed the final crop, the THC level in some of the strains was up as much as 30% compared to the buds harvested normally.

The same is also true for Terpines. During the day, these evaporate and are replenished during the night cycle. These are what make your plants smell amazing and also add to the entourage effect. After 48 hours in darkness, your plants REALLY begin to smell, and this is why.

How long is enough?


If you're in a rush, the best time to harvest is right before the lights are due to come on. This ensures no cannabinoids have been degraded yet.

You'll barely notice any difference after 24 hours darkness either as the process has only just started to elevate but you can do it for 48 - 72 hours and get good results. Some people claim they've done it for up to a week before, but I haven't tried this at all.

Just remember that the longer you leave it... The less solid your buds become.

Mould & Bud Rot


If you're going to try this... Make sure you don't water your plants so the soil or coco is dry before you do. Lower humidity = more THC and high levels of moisture in the air or ground can lead to Mould and the dreaded bud rot!

Discussion


Have you tried this? Do you swear by it? What were your results? I do it every time although I don't remember if it does make things better, it just makes a lot of sense to me to do it this way.
allright dave ,
i think its another one of those old wives tales,or old stoner tales as all the stuff about trichomes changing/replacing overnight is just nonsense whilst its true light degrades thc to cbn in theory you might save a tiny amount of thc from damage it in reality is so minimal as to be immaterial to the final potency,its simple enough to show just use your loupe or usb scope and photo the same trichome over a given period and you can see for yourelf how little and slow any change occurs,if nothing else i guess it might save a little electric but as to its effect on potency or thc levels theres so little to be gained id not bother myself,push them till chop as photosynthesis requires light.
nice looking buds you got hanging,good work :nice:
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Re: Dark period before harvesting.... Is it a myth?

Post by Ancient.Soul.Grown »

Great question....

I personally give them the 3 days dark prior to chop.

One final deep chill sleep before they go over rainbow bridge.

Again you need to make sure you have plenty of air movement and pots are fully dried out or at the 5 to 10% mark.

Just 1 step in many for creating bangin flower.

ASG
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duke (Thu Nov 18, 2021 8:08 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by MommaB »

I've read about this but must admit I've not ever tried it. Very interesting read!
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Re: Dark period before harvesting.... Is it a myth?

Post by JJ »

I do this too,,,,why,,?? So I believe in the dry pot theory tho
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duke (Thu Nov 18, 2021 8:09 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by Treetrunk »

I grow in bubblers and my usual method is drain the tank and give it 12 hours lights on and off then chop.
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duke (Thu Nov 18, 2021 9:02 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by KD »

duke wrote:
Thu Nov 18, 2021 4:51 pm
KD wrote:
Mon Nov 15, 2021 10:22 am
The Theories


There's a few theories about the best way to harvest your buds, including keeping them in up to 72 hours of darkness before the actual chop. But is it all nonsense?

Image

Thrichomes containing THC, among all the other cannabinoids, are believed to be produced as the plants way to protect itself from the effects of harmful UV radiation from the sun and other mildly stressful environmental factors. Suddenly turning off the sun for a few days is said to increase THC due to a stress response.

Another theory is that it evolved from the plants need to pollinate before winter. As the nights grow shorter, the plants produce more and more trichome covered buds in the hope of being pollinated and producing seeds. This doesn't make sense as no one can switch off the sun for days at a time in order for this evolution to happen.

Finally, the theory that makes most sense to me, is that cannabinoid levels fluctuate over 24 hours. They peak just at the end of the dark period and are degraded during the day as they protect the plant from UV radiation. During the night, the plants replenish the degraded trichomes ready for the next day. By extending the dark period, the plants should be producing more cannabinoids than normal.

The Science


I can't actually find the scientific papers that prove any theory but the story goes that there were experiments carried out by the Stichting Institute of Medical Marijuana (SIMM). In the experiment they harvested half of their plants as normal, and kept the other half in darkness for 72 hours. When they later analyzed the final crop, the THC level in some of the strains was up as much as 30% compared to the buds harvested normally.

The same is also true for Terpines. During the day, these evaporate and are replenished during the night cycle. These are what make your plants smell amazing and also add to the entourage effect. After 48 hours in darkness, your plants REALLY begin to smell, and this is why.

How long is enough?


If you're in a rush, the best time to harvest is right before the lights are due to come on. This ensures no cannabinoids have been degraded yet.

You'll barely notice any difference after 24 hours darkness either as the process has only just started to elevate but you can do it for 48 - 72 hours and get good results. Some people claim they've done it for up to a week before, but I haven't tried this at all.

Just remember that the longer you leave it... The less solid your buds become.

Mould & Bud Rot


If you're going to try this... Make sure you don't water your plants so the soil or coco is dry before you do. Lower humidity = more THC and high levels of moisture in the air or ground can lead to Mould and the dreaded bud rot!

Discussion


Have you tried this? Do you swear by it? What were your results? I do it every time although I don't remember if it does make things better, it just makes a lot of sense to me to do it this way.
allright dave ,
i think its another one of those old wives tales,or old stoner tales as all the stuff about trichomes changing/replacing overnight is just nonsense whilst its true light degrades thc to cbn in theory you might save a tiny amount of thc from damage it in reality is so minimal as to be immaterial to the final potency,its simple enough to show just use your loupe or usb scope and photo the same trichome over a given period and you can see for yourelf how little and slow any change occurs,if nothing else i guess it might save a little electric but as to its effect on potency or thc levels theres so little to be gained id not bother myself,push them till chop as photosynthesis requires light.
nice looking buds you got hanging,good work :nice:
When you say it's nonsense, do you actually have any evidence to support that other than "look at a trichome"

We can't see what's happening inside them on a molecular level with a loupe.

Here's what I do know....

Tuesday I turned my flower tent off... The car in filter was struggling slightly. Today, I've chopped her and not only does my house smell like I don't have a filter, but opening the tent is the strongest smell I've had off her yet. You can't see the terps but you sure can smell em!
Ancient.Soul.Grown wrote:
Thu Nov 18, 2021 6:03 pm
Great question....

I personally give them the 3 days dark prior to chop.

One final deep chill sleep before they go over rainbow bridge.

Again you need to make sure you have plenty of air movement and pots are fully dried out or at the 5 to 10% mark.

Just 1 step in many for creating bangin flower.

ASG
Airflow and dry pots are a must yeah!
Momma bear wrote:
Thu Nov 18, 2021 6:38 pm
I've read about this but must admit I've not ever tried it. Very interesting read!
Try it and see if you think it helps. Can't hurt :)
JJ wrote:
Thu Nov 18, 2021 7:43 pm
I do this too,,,,why,,?? So I believe in the dry pot theory tho
Dry pot theory? Is that the one where fluid in the plant returns to the pot due to osmotic pressure and the lack of photosynthesis drying moisture out of the pot?
Treetrunk wrote:
Thu Nov 18, 2021 8:17 pm
I grow in bubblers and my usual method is drain the tank and give it 12 hours lights on and off then chop.
Drain the tank? Why do you do this? Does it help?
These users thanked the author KD for the post:
biosynthetic (Fri Nov 19, 2021 3:27 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by Treetrunk »

KD wrote:
Fri Nov 19, 2021 1:02 am
duke wrote:
Thu Nov 18, 2021 4:51 pm
KD wrote:
Mon Nov 15, 2021 10:22 am
The Theories


There's a few theories about the best way to harvest your buds, including keeping them in up to 72 hours of darkness before the actual chop. But is it all nonsense?

Image

Thrichomes containing THC, among all the other cannabinoids, are believed to be produced as the plants way to protect itself from the effects of harmful UV radiation from the sun and other mildly stressful environmental factors. Suddenly turning off the sun for a few days is said to increase THC due to a stress response.

Another theory is that it evolved from the plants need to pollinate before winter. As the nights grow shorter, the plants produce more and more trichome covered buds in the hope of being pollinated and producing seeds. This doesn't make sense as no one can switch off the sun for days at a time in order for this evolution to happen.

Finally, the theory that makes most sense to me, is that cannabinoid levels fluctuate over 24 hours. They peak just at the end of the dark period and are degraded during the day as they protect the plant from UV radiation. During the night, the plants replenish the degraded trichomes ready for the next day. By extending the dark period, the plants should be producing more cannabinoids than normal.

The Science


I can't actually find the scientific papers that prove any theory but the story goes that there were experiments carried out by the Stichting Institute of Medical Marijuana (SIMM). In the experiment they harvested half of their plants as normal, and kept the other half in darkness for 72 hours. When they later analyzed the final crop, the THC level in some of the strains was up as much as 30% compared to the buds harvested normally.

The same is also true for Terpines. During the day, these evaporate and are replenished during the night cycle. These are what make your plants smell amazing and also add to the entourage effect. After 48 hours in darkness, your plants REALLY begin to smell, and this is why.

How long is enough?


If you're in a rush, the best time to harvest is right before the lights are due to come on. This ensures no cannabinoids have been degraded yet.

You'll barely notice any difference after 24 hours darkness either as the process has only just started to elevate but you can do it for 48 - 72 hours and get good results. Some people claim they've done it for up to a week before, but I haven't tried this at all.

Just remember that the longer you leave it... The less solid your buds become.

Mould & Bud Rot


If you're going to try this... Make sure you don't water your plants so the soil or coco is dry before you do. Lower humidity = more THC and high levels of moisture in the air or ground can lead to Mould and the dreaded bud rot!

Discussion


Have you tried this? Do you swear by it? What were your results? I do it every time although I don't remember if it does make things better, it just makes a lot of sense to me to do it this way.
allright dave ,
i think its another one of those old wives tales,or old stoner tales as all the stuff about trichomes changing/replacing overnight is just nonsense whilst its true light degrades thc to cbn in theory you might save a tiny amount of thc from damage it in reality is so minimal as to be immaterial to the final potency,its simple enough to show just use your loupe or usb scope and photo the same trichome over a given period and you can see for yourelf how little and slow any change occurs,if nothing else i guess it might save a little electric but as to its effect on potency or thc levels theres so little to be gained id not bother myself,push them till chop as photosynthesis requires light.
nice looking buds you got hanging,good work :nice:
When you say it's nonsense, do you actually have any evidence to support that other than "look at a trichome"

We can't see what's happening inside them on a molecular level with a loupe.

Here's what I do know....

Tuesday I turned my flower tent off... The car in filter was struggling slightly. Today, I've chopped her and not only does my house smell like I don't have a filter, but opening the tent is the strongest smell I've had off her yet. You can't see the terps but you sure can smell em!
Ancient.Soul.Grown wrote:
Thu Nov 18, 2021 6:03 pm
Great question....

I personally give them the 3 days dark prior to chop.

One final deep chill sleep before they go over rainbow bridge.

Again you need to make sure you have plenty of air movement and pots are fully dried out or at the 5 to 10% mark.

Just 1 step in many for creating bangin flower.

ASG
Airflow and dry pots are a must yeah!
Momma bear wrote:
Thu Nov 18, 2021 6:38 pm
I've read about this but must admit I've not ever tried it. Very interesting read!
Try it and see if you think it helps. Can't hurt :)
JJ wrote:
Thu Nov 18, 2021 7:43 pm
I do this too,,,,why,,?? So I believe in the dry pot theory tho
Dry pot theory? Is that the one where fluid in the plant returns to the pot due to osmotic pressure and the lack of photosynthesis drying moisture out of the pot?
Treetrunk wrote:
Thu Nov 18, 2021 8:17 pm
I grow in bubblers and my usual method is drain the tank and give it 12 hours lights on and off then chop.
Drain the tank? Why do you do this? Does it help?
Basically drain the tank and leave the lights on for one more cycle.
When I come to chop the next day the roots and tank are bone dry. It helps getting the roots out of the pots too.
Not sure if it helps or does any good it's just the way I do it. I use all the roots and trim for compost. Mixing it with seaweed and garden waste. I'm going to use it for some outdoor auto's in the summer.
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KD (Fri Nov 19, 2021 8:52 am) • biosynthetic (Fri Nov 19, 2021 3:27 pm)

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Re: Dark period before harvesting.... Is it a myth?

Post by Hmr81 »

I tried it once, didnt seem to make any difference that i could tell so haven't ever done it again tbh. Maybe there is something to it, maybe there isn't but it just slowed me getting into the drying phase and i dont have time for that lol.
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KD (Fri Nov 19, 2021 8:52 am) • 2-Scoops (Fri Nov 19, 2021 1:32 pm)
From the Garage of HMR
No Current Grow on, Point5 has the tent and is doing her lovely thing.

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Re: Dark period before harvesting.... Is it a myth?

Post by KD »

Treetrunk wrote:
Fri Nov 19, 2021 7:20 am
KD wrote:
Fri Nov 19, 2021 1:02 am
duke wrote:
Thu Nov 18, 2021 4:51 pm

allright dave ,
i think its another one of those old wives tales,or old stoner tales as all the stuff about trichomes changing/replacing overnight is just nonsense whilst its true light degrades thc to cbn in theory you might save a tiny amount of thc from damage it in reality is so minimal as to be immaterial to the final potency,its simple enough to show just use your loupe or usb scope and photo the same trichome over a given period and you can see for yourelf how little and slow any change occurs,if nothing else i guess it might save a little electric but as to its effect on potency or thc levels theres so little to be gained id not bother myself,push them till chop as photosynthesis requires light.
nice looking buds you got hanging,good work :nice:
When you say it's nonsense, do you actually have any evidence to support that other than "look at a trichome"

We can't see what's happening inside them on a molecular level with a loupe.

Here's what I do know....

Tuesday I turned my flower tent off... The car in filter was struggling slightly. Today, I've chopped her and not only does my house smell like I don't have a filter, but opening the tent is the strongest smell I've had off her yet. You can't see the terps but you sure can smell em!
Ancient.Soul.Grown wrote:
Thu Nov 18, 2021 6:03 pm
Great question....

I personally give them the 3 days dark prior to chop.

One final deep chill sleep before they go over rainbow bridge.

Again you need to make sure you have plenty of air movement and pots are fully dried out or at the 5 to 10% mark.

Just 1 step in many for creating bangin flower.

ASG
Airflow and dry pots are a must yeah!
Momma bear wrote:
Thu Nov 18, 2021 6:38 pm
I've read about this but must admit I've not ever tried it. Very interesting read!
Try it and see if you think it helps. Can't hurt :)
JJ wrote:
Thu Nov 18, 2021 7:43 pm
I do this too,,,,why,,?? So I believe in the dry pot theory tho
Dry pot theory? Is that the one where fluid in the plant returns to the pot due to osmotic pressure and the lack of photosynthesis drying moisture out of the pot?
Treetrunk wrote:
Thu Nov 18, 2021 8:17 pm
I grow in bubblers and my usual method is drain the tank and give it 12 hours lights on and off then chop.
Drain the tank? Why do you do this? Does it help?
Basically drain the tank and leave the lights on for one more cycle.
When I come to chop the next day the roots and tank are bone dry. It helps getting the roots out of the pots too.
Not sure if it helps or does any good it's just the way I do it. I use all the roots and trim for compost. Mixing it with seaweed and garden waste. I'm going to use it for some outdoor auto's in the summer.
They'll love that! Good idea dude
Hmr81 wrote:
Fri Nov 19, 2021 8:22 am
I tried it once, didnt seem to make any difference that i could tell so haven't ever done it again tbh. Maybe there is something to it, maybe there isn't but it just slowed me getting into the drying phase and i dont have time for that lol.
Lol fair enough 😁
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