RH not very crucial, but it will decrease bud size if too low or high. You could put a bucket of water in the room to evaporate and increase humididty. I see you said grow box, so put a couple beer cups of water in there to evaporate by the plants. You can also mist the plants when the lights are off, but when they are on the water droplets on the leaves can cause light burn.
Dr.Hashman Reviewed by Dr.Hashman on . Increasing RH% Levels? My plants are in a grow box in the early grow stages, and the RH% level has been about 35-45%, I was wondering if there was a good way to increase the humidity to 50-60% as is recomended, or if it is even necessary. Rating: 5