I just came across Albizia julibrissin 'Summer Chocolate' (mimosa tree) on a website; I HAVE to have it!! BUT it's rated zone 7, & I live in zone 5... Can this plant be grown indoors/as a houseplant by any chance??? As in, have it outdoors in a pot in the summer, & then bring it in to over-winter indoors? Also, the size given on the website is 20' x 15'; would growing it in a pot keep it smaller/more manageable?? If so, HOW small? Would I also need to prune it to control its size? If so, how?
Mimosa (Albizzia) would not make a good houseplant. It requires a dormant period in winter. However, you might be able to grow it in a container and move it into an unheated garage or similar location for the winter. Ideally, it should stay close to freezing to keep the tree dormant through the winter months.
Growing it in a container will confine the root system and limit its size, possibly to half its full potential. It would need some pruning to keep it in check as well. Keep some of the oldest branches pruned off completely, and cut back tips of the rest to manage its size.