Here in w.va. redbuds are every where.they are pretty trees bloom befor any leaves.these have too big leaves for bonsai unless the tree is3 ft or more for size of the foliage..hpoe this helps i do not know if they would reduce.the purple flowers are really pretty..john

This is what a redbud bonsai would look like:

http://www.scenicnursery.com/archives/mp0715f.jpg

http://ecx.images-amazon.com/images/I/31qLelM1O0L.jpg