Depends on the size of the area. 1500 lumens per sq. foot. There are other factors aswell such as CO2, spectrum, and envirnment. (god damn I wrote you last night and my posts are still getting erased, WTF)

Mothers will last forever on 24 hours light. That is why 18/6 is no good. The hormones get burnt out.
karmaxul Reviewed by karmaxul on . Lumens per plant? How many lumens would it take for 1 plant to live a happy life? (surrounded in mylar) Rating: 5