If your region is subject to ice storms and heavy snows, then I recommend providing winter protection for most deciduous flowering shrubs. You can shelter flowering shrubs under a lean-to or similar structure. For a full article on the subject, please consult my tutorial on providing winter protection for shrubs with shelters. Through pictures, this tutorial shows you how to build a simple structure within which to house your deciduous bushes for the winter.
In another FAQ, I discuss the matter of providing evergreen shrubs with winter protection.
Watering trees and shrubs properly in autumn is another way to "winterize" them, as I discuss in my FAQ on watering trees in fall.