Question
A friend's rose of sharon sets buds, but for the last several years, they have never opened, but instead start to show color and then drop off the plant.  The plant itself looks very healthy.  We can't figure out why the buds don't open.  Hope you can help.

Answer
Hi Leroy,
Thanx for your question.  Buds can drop from lack of water, too much fertilizer and sometimes pests.  Take a few of the buds that have dropped or are about to drop and place them inside plastic baggies.  Wait a few days and you may find insects that have been infesting the flowers.  You may want to take a sample in to your local county extension agent.  Japanese flea beetles seem to like them.  If you give me your county, I can give you a contact point.   hope this helps.
Tom