Will they grow in South Florida or do they need to winter over?
Rose of Sharon
Certified GKH Gardening Expert
Generally, they will want to have a dormancy, but this does not mean that they need it. You can grow them in your area as long as you keep them from getting overly hot in the summer.
Here is an article for more information on the plant: https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/rose-of-sharon-bush.htm