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VPD: The Final Stages Of Life
GeMannstarted grow question 4 years ago
Lets talk about VPD in flower, Am I supposed to follow VPD when in flower. humidity 30-40% temps 70-75F will give me a VPD of 1.5-1.65 {leaf temps -2,-3 cooler} that would be on the high end. do I keep the temp/RH or try to follow VPD. {just in flower}......74F-36% RH
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CRiSPrGrowanswered grow question 4 years ago
The VPD charts for cannabis in flower are all skewed in a way to make it “better” to have low humidity . But actually why would that be the case ? Well, it wouldn’t be for any other reason than that low humidity is common practice (to reduce the likelihood of mold) . High humidity in flower as well as in veg is better for the plant perspiration , but all the vpd charts say low humidity. So if you want optimal vpd keep the 1.0 but if you want a safe flowering (and you should!) go with the higher VPD . Hope this helps ! 🚀
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Organomananswered grow question 4 years ago
Vapour-Pressure Deficit for those playing along at home!
Basically about plant transpiration rates and CO2 assimilation.
I'm not sure cannabis cultivation needs to be so complicate, VPD is really splitting hairs and I can't see how it could or would affect cannabinoid quality, quantity or synthesis. Anyway, a high VPD is required during flowering.
Hope this helps,.........
Organoman.
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