Answer: It's the hollyhock weevil, says Whitney Cranshaw, extension entomologist at Colorado State University in Fort Collins. This weevil only feeds on hollyhock plants, so it won't affect your other flowers, he says. The adult weevils overwinter in hollyhock seedpods and plant debris on the soil, emerging in mid June to feed on the leaves of young hollyhock plants. Small puncture holes in the leaves in spring are a sure sign of their presence. says Cranshaw. As the flower buds develop, the 1/8 inch long, grayish blue adult uses its long snout to puncture them and lay eggs in the developing seedpods. The eggs hatch and the larvae feed on the seeds until fall. There in one generation a year in Colorado. Cleaning and destroying all garden debris in fall will dramatically lessen the population and the damage the following year, says Cranshaw. If you aren't concerned about saving seeds from your hollyhocks, you can destroy the seedpods after flowering, but before the pods mature killing the weevils inside. If you're saving seeds, inspect the flower buds in summer and shade any weevils off into a can of soapy water. You can also spray with rotenone or Sevin as weevils appear on the buds, he says.
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