I have tons of rose of Sharon bushes and you can replant them at any time,spring or summer. One word of advise, they do re seed themselves everywhere. It has become a major task to pull up the baby ones before they take root, and they do root quickly. I have planted pinks, purples and whites all together and when they bloom they are beautiful. I have started to cut the tops off so they do more of a bushing out than a tree. I have an entire border that's about six feet tall as a "fence" in my backyard. Good luck with them.