How And When To Prune A Smoke Bush/tree?

Question

I have had it since 2017 and have prune branches only for shape, but it seems to have grown sucker-like stems.

Answer 1

Suckers can be removed at any time. This article should help:

https://www.gardeningknowhow.com/ornamental/trees/smoke-tree/pruning-smoke-trees.htm