@Mark0427 hey Mark I had to do some digging, because it’s been a while since I refreshed my memory on this practice but I’m glad you did.
I had believed the 3 days but now I’m going to be doing 2 days, since information has changed.
We know darkness helps produce higher thc concentration, it does this in a couple different ways one of which is light degrades thc but the buds ned light to produce flowers because thc is Sunscreen basically. So by allowing the plant a boost of dark time to grow but not have the thc degraded helps.
On another forum a senior member claims
“The scientific reasoning behind the dark period before harvesting is to allow the starches and sugars to drop to the roots. The less sugars and complex carbohydrates in the flowers, the less time we have to cure for the best flavor. I’ve read 48-72 hours AND you chop in dark. If you allow the plants to see light before chopping after 3 days of darkness, the sugars and starches will rush up the plant to fuel photosynthesis within the plant within two minutes of exposure to light.”
There is also circulation of a study that cannot be found by many who have searched for it, the claim is
" The Stichting Institute of Medical (SIMM), the first company to sell through the pharmacies of Holland, has been investigating the medical possibilities of cannabis, together with TNO laboratories and the University of Leiden.
One of their discoveries has been that to keep the ripe plants in the dark before harvesting could increase their potency. growers separated a crop of mature plants, harvested half of them and kept the other half in absolute darkness for 72 hours before cutting and drying. Analysis of the resulting dried buds showed that some varieties had seen an increase of THC of up to 30%, while CBD and CBN remained the same."
The best current real proof we have is here, although again its not a perfect study and is small scale its combined evidence.
There are also other backyard/ forum experiments that compare no darkness to darkness looking at tricombs, so in general it is agreed darkness helps with potency. Although those that simply do a smoke test often don’t notice a difference but that’s not very scientific.
We know terpenes are highest when a plant is fresh, this is why plants are flash frozen for live resin production etc.
In summary I would suggest 48hr of darkness.
Thoughts
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