I ran across a great Begonia dregei Bonsai on Facebook of all places. David Bennett has an incredible Begonia tree. I did a search on Google and found a few starter plants. They are supposed to be a fast grower. So I purchased a tree from a seller in Wisconsin and they mailed a few days ago (Jan 2020). The tree arrived alive but there was some damage to the top growing shoots. The tree should survive ok. This is one tree where it would be wise not to let a frost hit it. It would be awful for the whole tree to die down to the bulb. The bulb starts to enlarge as the plant grows larger, so the goal should be not to let the top of the plant ever die back down to the bulb. Starter plants are not real expensive so this would be a good tree for a beginner. David Bennett is a great Bonsai pot maker by the way.
Begonia dregei by Plant Rescue
Photo courtesy of David Bennett. That’s David with the tree.