400 watts will do it
the number of plants you grow really depends on the style of grow your going with weather it be lst, scrog, sog or whatever and your amount of veg time.
you could grow one monster
2-4 smaller plants
you could even grow 50 single colas with a sog(sea of green)
wman44 Reviewed by wman44 on . Grow Box For Single Plant?? Need Advice!! Hey guys I am a first time grower and I was wondering if anyone out there could help me out with this. I want to build a grow box for a single plant. I'll make it out of 3/4" plywood and about 3' wide by 3' deep by 6' high. I want my plant to grow to height of about 5' so I can get more buds than if I built it shorter, just wondering if it would be worth it to build it that high or not. As for lights, I was just going to put several cfl's around the inside of the box. Maybe 6 at the ceiling and Rating: 5