Answer: It sounds like Japanese beetles have found your coneflowers. If so, these beetles munch for about four to six weeks in July and August; infestations are heavier some years than others. Luckily, the damage doesn't usually kill the plants. Some gardeners simply tolerate the damage, some hand pick the beetles and drop them into soapy water. Another option is to try the pheromone traps, carefully following the instructions as to locating the traps so as not to inadvertently attact even more beetles to your garden. Finally, if it is really severe, you might try spraying neem on a regular basis according to the label instructions.
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