RH soars when lights go off

Every time my lights go out my RH goes from 50ish to 68 in less than an hour. What can I do besides install dehumidifier? They are flowering and I don’t want mold. I have a small fan in center of them blowing up and a oscillating fan working the branches. I’ve tried with exhaust off no help exhaust on no help

Your leaves are perspiring and your lights aren’t burning it off. You hygrometer is probably close to the plant so you have a microclimate of high humidity around the plant. More ventilation and air flow even when lights are off will lower the humidity around the plants.


So should I be worried? I am flowering almost 5 weeks in. It’s a 4 hour lights out. I have a intake fan that I usually don’t use because it causes tent to pillow but I think I’ll program that to turn on when lights go out. Do you think that will help? Should I move the hygrometer? It’s in the canopy

Run your exhaust fan always. Itll keep new air moving and lower humidity


suggest you set intake and exhaust fans to run for an hour after lights out.

you could also open the sides if you have a tent or screen…