Humidity in veg stage... i've seen the charts but what about mold?

Hey folks, I see a lot of charts and info that in veg 60-70% RH is good. 2 questions arise from that for me.

  1. I’ve read that over 40% humidity and you have to watch out for mold, particularly white powder mold. How to prevent? Is it as easy as making sure you have good air flow in the tent?

  2. How are you raising the humidity in your tent. My room is 40% RH and I put a humidifier right by the intake but i still struggle to get it that high. Im hitting 55%. Should I put the humidifier in the tent? I suppose I can invest in one of those outlets that activate based on RH or Temp.

The other issue is in the same room I have 2 small tents for veg and 1 big tent for flowering so I could up the whole room, but then I would have to dehumidify in the big tent.

Set to follow because my vpd chart for my setup is pretty high too; and I can Only get it that high after watering.

Good air exchange and air flow are the two biggest factors of any kind of mold issues, regardless of humidity levels.


From what I understand about white powder mold is that it mostly depends if the general area where you live/grow is already saturated with spores, so basically if you see a lot of outdoor plants being effected by it then it’s an issue , and I have a hard time getting RH indoor to rise too, the best method I have so far (with no humidifier)is I just put damp cloth hand towels through the handles of my fabric pots and let them evaporate(raised my rh from 45 to 55 so far)


Do like me, grow in a garage that has panels and stuff missing. Oh, and in Florida where it’s always raining. I dont even check mine. I know it’s high. I’m actually more worried about flowering! Lol.

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