Answer: There are several insects that will nibble on these flowers including Japanese beetles. For these, a neem-based spray may be effective as can hand picking if the infestation is not too severe. To be honest I have never seen worms inside these flowers, but in this exceptionally hot and dry year we are seeing many unusual infestation problems. Since the worms are inside, probably the most effective control would be to cut off and remove those blooms and be sure to put them in the trash rather than the compost pile. This fall, be very careful to clean up, remove and destroy plant debris to reduce the chance of the pests overwintering in the garden. You might also check with your County Extension to see if they can identify the specific pest and suggest controls.
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