I've had mini's in pots in the past. I take them indoors for the winter and they do fine for a couple of years. Then, they become too pot bound, even though I use a fairly large pot. Should I take them out of the pots every few years and trim the roots back? I would then have to trim the top back to compensate, of course. Would this make them last longer in pots? I don't want to move them to larger pots, as they become too heavy to move inside.