We have 6 Rose of Sharon plants in our yard here in Garner, N. C. They have lavender double blooms. A couple of years ago, there appeared on one of the branches a pure white bloom. Both colors on the same branch, only a couple of inches apart. In the twenty or so years that we have had these plants, nothing like this has ever occured, either before or since. The question is: just how rare is this? Since it has never happened before, I assume it must be pretty unusual.