Here's a short explanation on vpd.Btw, while it may be too soon to make a definitive statement, switching lights to 20/4 seems to be agreeing with the plants. They appear a little less droopy. Additionally, In your thread, you routinely refer to VPD. Not knowing much about that, it was easy for me to maintain a higher VPD in my closet. When I switched to the tent, I allowed RH to go down and didn't think much about it. I have since put another humidifier in the tent and have rh up around 60-70%. Just based on visuals, the gals seem to be comfortable in that range. I am at 34-42 days.
Any articles/input on rh/VPD for different growth stages is appreciated. I know others say they don't pay attention to rh, however I am seeing improvement w/higher rh. I do understand that as they progress further into Flower, I need to pay attention/prevent mold. It is VERY easy to lower RH. I'm in the desert.
VPD Chart (Vapor Pressure Deficit) - Perfect Grower Knowledge Database
VPD Chart (Vapor Pressure Deficit) by Perfect Grower
www.perfectgrower.com
If you want more, just search for VPD and cannabis.
Like you said, just remember in late flower to keep mold out of the picture, keep your humidity down and adjust your temps to maintain a good vpd. If you can't maintain a high vpd, concentrate on keeping humidity down.
It's just a guide to grow the best canna you can. You can still grow good canna otherwise.
I've known about vpd for decades, but with growing outdoors, I had no control of it. It went to the back of my brain. Well over halfway on my first indoor canna grow, this forum brought it to the forefront of my thought process.