You can definitely fill up 4 x 8 with 3 plants. Start LST early, top/FIM them, and feed a little high in nitrogen but don't over nute. Keep lights close, and keep the area well ventilated. 2 months your plants will be a jungle. Drop in the screen on the 6 week in veg. Once you flip to bloom they will stretch through the screen opening and have even tops. Until the switch push down any branches that come through back under the screen. Keeping them all down there will help distribute the plants hormone to speed up side branch growth which in turn will fill up the screen much faster.
Strange how every states has their own plants limit. Then again, some plants is better than having none...good luck!
Strange how every states has their own plants limit. Then again, some plants is better than having none...good luck!