I just checked the roots out on a couple of them & they haven't went that deep yet.I'd say there probally around 5 inches down and plenty of room on the sides,so they have plenty of grow room for sure!What would be & idea size to start my 12-12?If they kep growing good like they are could i still go say around 2 1/2 feet & then put them into flowering?I took a small ruler & went around them and they will move if you start moving the soil so there not very deep.