I'd do it at like 18" (18" x 2 = 3ft) that's probably closer, but with 3 footers you need side lighting, hard for anything but a 500-1000w light to penetrate that far from the top.
4x5 Reviewed by 4x5 on . Extra Foot? I want 3 Foot Plants, and from expereince those lil guys like to grow more even after 12/12 is force. So if i bud it at 2 ft will it end up about 3 ft in the end? Rating: 5