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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Cosmos > Holes in flowers

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Cosmos > Flowers > Holes in flowers

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  • Cucumber beetles 1
  • Cucumber beetles 2
  • Cucumber beetles 3

Cucumber Beetles
Diabrotica undecimpunctata, Acalymma vittata

  • Active from June through September
  • Beetles chew on flowers and foliage
  • The spotted cucumber beetle adult is 1/4 inch long, bright yellow-green body with 12 black spots
  • The striped cucumber beetle adult is 1/5 inch long, bright yellow body with 3 even black stripes
  • More information on cucumber beetles
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  • Japanese beetle 1
  • Japanese beetle damage 2
  • Japanese beetle 3

Japanese Beetle
Popillia japonica

  • Adults present late June/early July to August
  • Chews on leaves
  • Chews holes in blossoms
  • Adults are a brilliant metallic green with copper-brown wing covers, approximately 3/8 inches in length, five white patches of hairs on each side of the abdomen, and two patches of white hair on the tip of abdomen
  • More information on Japanese Beetles

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