Grow Box Lighting and Venting

by Ron
(NC)

I've built a 36x28x60 grow box. I'm going to be running a 200w fluorescent light and I'm considering 2 88mm fans in the upper portion of the box (one to pull and one to push). I also have a small oscillating fan inside the box to keep it all moving. Does this sound adequate to you? Thanks for the insight, Ron.

Answer: Ron- in general, I recommend a minimum of 40 watts of light per square foot to grow most sun loving plants. If you are planning on growing lettuce, spinach, or herbs, your 200 watt fluorescent light should do fine. Otherwise, you will have to supplement the lighting.

The more lighting you have, the more heat you will have to deal with. Two 88mm fans will likely not be good enough. As a general rule, the exhaust fan should be able to completely exhaust the air inside the grow box in 5 minutes or less. Step by step instructions on how to pick the right size exhaust fan can be found on my exhaust fan calculator page. In general, keep the air intake low and the air exhaust high, and follow the directions in the link above.