I live in central NC. My hatchlings every year are born in late summer/early fall. The following spring after we have not had a frost for 3 weeks I put them outside. That's it, they live outdoors from that moment on and will not be inside again unless I were to need them in for some reason of my own. My one holdover from last year would be out by now himself, but I would like to keep him in his own pen and need to put one together for him.
I keep easterns and three-toeds this way (and 3 that are mutts)