Hibiscus syriacus is hardy in zones 5-9 and can withstand cold temperatures and frost. However, it is important to protect the plant from strong winds and heavy snow or ice accumulation. To do this, you can wrap the plant in burlap or cover it with a protective barrier such as a tarp or plastic sheeting. It is also a good idea to mulch around the base of the plant to help insulate the roots from the cold. In the spring, remove any winter protection and prune the plant as needed to promote healthy growth.
