Answer: Rose of Sharon needs full sun in order to bloom well. If it isn't getting full sun, that might be why the buds do not open. Another possibility is an insect called a gall midge. If the larvae are feeding on the flower buds, they won't open. You can check the unopened buds for holes, or you can pick a few and open them up to see if there's anything in there. Or, place some buds in a sealable plastic bag. After a day or two, you may see the very small yellowish worm-like larva on the plastic. Control the midge affecting buds with Orthene sprays as needed. Hope this helps.
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