i have a young Rose of Sharon that has a double Pink and White flower.
I have lost the label but it does sound like the Danica one you mentioned. Are you interested in cuttings of it? Also have a flower, very large, 5" but sterile of a white one from USDA. Again i have lost the flower label but it is very dramatic with dark green leaves against the pure white flower. I can only give cuttings of the later because it is sterile bud could send a selection( marked ), of the 4 or five best Rose of Sharons I have. arfitz