[purplelove]

Hey, what's up to all my growers out there? I'm growing some auto flowers. And this time around, I wanna do it perfectly. I'm just now learning about VPD after years of growing, there's a lot of stuff I don't know, can somebody tell me the exact environment that I need to set my tent up? I'm growing auto flowers right now. I have the full setup humidifier. I got the light. I got the fans, I got. The extractor you name it. I just wanna know the perfect environment to set it up in

 

[GrowSense]

There's no single perfect number, but there's a tight enough window that you won't be guessing. VPD just combines temp and RH to tell you how hard the plant is pulling water, and autos don't care about the second decimal.

Seedlings to about week 2: 75 to 80F, 65 to 70% RH, VPD around 0.6 to 0.8 kPa. Veg, roughly weeks 2 to 4: 75 to 82F, 55 to 65% RH, VPD 0.9 to 1.1. Flower from about week 4: 72 to 80F, 45 to 55% RH, VPD 1.1 to 1.4, then ease RH down to 40 to 45% for the last couple weeks to keep bud rot away. Autos run on their own clock, so drop RH when the first flowers show instead of waiting on a date.

Lights off, keep temp within about 10 degrees of lights on and don't let RH spike. Put your hygrometer at canopy height, not on the tent wall. Leaf surface runs a touch cooler than the air under an LED, so slightly warmer air isn't a problem.

What light are you running, and how big is the tent?