Tag Archives: lighting. calculating light needed

Lighting My Grow

I have a 3ft x 3 ft grow area. How much light do I need? I need to light it at the least cost possible. Thanks in advance for your help.

— Orvin in Utah

Hello Orvin,

The general grow light standard is that you want at least 50 incandescent watts of light per square foot of growing space.

Your 3 x 3 space is 9 ft.², so if you multiply 9×50, you get 450 watts of incandescent equivalent light needed.

You can mix and match the lights you have in order to come up with at least 450 equivalent watts.

Here is a link to how to build your own grow light for less money.



Dr. Grow