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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Hardy Geranium > Spots on leaves

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Hardy Geranium > Spots on leaves

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  • Image: fourline bug 1
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Fourlined plant bug

  • Occurs May to early July
  • Feeding causes brownish or sunken spot on leaves
  • Nymphs are red or red and black; Adults are greenish yellow with 4 black stripes, 1/4 to 1/3 inch long
  • More information on Fourlined plant bug...
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  • Image: rust 1
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Rust
Puccinia and Uromyces species

  • Oval to round yellow leaf spots on the upper side of the leaf
  • Mature leaf spots are brown or orange in the center with a yellow border
  • Raised orange blisters on the underside of the leaf
  • Powdery orange spores rub off of lower leaf surface and can be seen on a white tissue paper
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  • Image: powdery mildew 1
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Powdery Mildew
Erysiphe cichoracearum

  • Powdery, fluffy, white spots or blotches on leaves, stems and flower parts
  • Tiny raised black dots may be visible within white spots late summer or early fall
  • Spots typically start on lower leaves but can spread to cover the entire plant
  • Severely infected leaves may be completely covered in white or grayish white fungi
  • In some cases, leaves become curled or twisted or turn yellow due to the infection
  • More information on Powdery Mildew...

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