Experts and BHG readers answer.
Coneflower Petal Problems
Thanks for writing. Are the flowers actually eaten or deformed? If they're eaten, it's likely an insect pest of some sort (there's a handful of insects that will eat coneflowers).
If they're deformed, it could be a disease called aster yellows, a virus, or the buds could be affected by herbicide drift. It's impossible for me to say fr sure without being able to see them.
---Justin, Senior Garden Editor, BHG.com