Good temp/humidity during veg or not?

I try to stay in the range 80F to 85F and 55% to 60% in veg. That's to the dry side of ideal on a VPD chart. In flower I try to make it a little drier.
Scynce_VPD_chart-01.png
 
Most VDP charts are DUMB!!! Because they don't relate to WHAT YOU ARE ACTUAL GROWING. Each type of plant has different Photosynthesis & Transpiration rates, for example a tomato plant grows the best, and produces the most fruit if a VPD of 0.80 kPa is maintained no matter what the environment temperature is. So, say you ran a light ON temp of 75F, and a light OFF temp of 66F, then your light ON RH percentage to maintain a VPD of 0.80 kPa at 75F would be 70% RH, then your light OFF RH percentage to maintain a VPD of 0.80 kPa at 66F would be 65% RH. Cannabis/Hemp plants are different than tomato plants, they grow best maintaining a VPD of 1.10 kPa, so if you ran a light ON temp of 75F, and a light OFF temp of 66F, then your light ON RH percentage to maintain a VPD of 1.10 kPa at 75F would be 65% RH, then your light OFF RH percentage to maintain a VPD of 1.10 kPa at 66F would be 50% RH.

Other notes...

Ones environment RH (%) should always match the environments temperature (C/F), based exclusively on the proper VPD/kPa rate for whatever type of plant one is growing!
 
piratebug said:
Most VDP charts are DUMB!!! Because they don't relate to WHAT YOU ARE ACTUAL GROWING. Each type of plant has different Photosynthesis & Transpiration rates, for example a tomato plant grows the best, and produces the most fruit if a VPD of 0.80 kPa is maintained no matter what the environment temperature is. So, say you ran a light ON temp of 75F, and a light OFF temp of 66F, then your light ON RH percentage to maintain a VPD of 0.80 kPa at 75F would be 70% RH, then your light OFF RH percentage to maintain a VPD of 0.80 kPa at 66F would be 65% RH. Cannabis/Hemp plants are different than tomato plants, they grow best maintaining a VPD of 1.10 kPa, so if you ran a light ON temp of 75F, and a light OFF temp of 66F, then your light ON RH percentage to maintain a VPD of 1.10 kPa at 75F would be 65% RH, then your light OFF RH percentage to maintain a VPD of 1.10 kPa at 66F would be 50% RH.

Other notes...

Ones environment RH (%) should always match the environments temperature (C/F), based exclusively on the proper VPD/kPa rate for whatever type of plant one is growing!
Click to expand...
It's a cannabis specific VPD chart from Scynce.
 
Have my temp/humidity consistently at 82.4/56.5. Seems to be working well for the plants. Just purchased an AC infinity duct fan w/ humidity and temp control. Should make things even easier!
 

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