I think canna will grow in cement to be honest with you. I pull chunks of mine up every year, just to keep it thinned out, and it fills in again within a year. Grows right up, inbetween cement border blocks and everything. Mine is in our native soil. I would say you can move it any time of the year, just make sure to keep it wet if you are going to move it now. mid to late September would probably be the best time to move it...just guessing here. I don't think you can kill the stuff!!!
