Answer: If these are new plants, they may be suffering heat or moisture stress due to not yet being fully rooted. This could cause the blooms to fall early. (Water to keep the soil slightly moist like a wrung out sponge, keep them mulched. Established plants however are very drought tolerant.) There are also a few pest problems that could cause this such as thrips. You might want to check with your local county extension and see if they can help you diagnose the problem more specifically. If it is something that can be controlled, they will have the most up to date recommendations as to what to use and how/when is best to apply it. Good luck with your shrubs!
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