There AUTOs. You can throw 20 of um under a 400.
You need to go with grow bags though, no wasted space. I have 9 in my 2x4 floorplan right now. And two of the plants (northern lights regular, vegged for a month) are 24-36inches tall and bushy. They finished stretching 2+ weeks ago. Three of the other plants in there are northern lights auto *(seeds are just poking through the dirt)* and 4 blueberry lowlifes. Im coming up on 3 weeks on the blueberry's and NONE are over 12inches, in fact 2 are 3inches tall and hairy.... You just dont know what youll get, no need to go bigger then 2 gallon pots, and please go with more then 5 plants. Try and wait a month after germing/planting your NL autos, buy another strain 5 pack, germ and plant them. Keep your grow going.