Q.Why Do My Royal Empress Trees Start Over Every Year?
All the leaves fall off in the fall and the canes or trunk dies, then the trees start with new sprouts again in the spring. So they really don’t get a chance to grow big. This is the third year I’ve had them.

Certified GKH Gardening Expert
This happens where they are not fully hardy. In these areas, they are treated as fast growing annuals. If you can offer more winter protection to the roots, this may not happen every year. Mulching, or burlapping the tree over the coolest parts of the winter can help.
Here is an article that will help you with the care of the tree: