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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Coleus > Leaves with spots, blotches, or other discoloration

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Coleus > Leaves > Spots, blotches, or other discoloration on leaves

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  • Powdery mildew 1
  • Powdery mildew 2
  • Powdery mildew 3

Impatiens Necrotic Spot Virus (INSV)

  • Symptoms are extremely variable
  • Stunted growth and wilting may occur
  • Leaf distortion; ringspots or black spots on leaves and stems; blackish/purplish coloration along leaf veins
  • Tip dieback and in some cases entire plant will collapse
  • Lab test needed to identify INSV since it is difficult to diagnose on symptoms alone
  • More information on INSV
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  • Powdery mildew on peony
  • Powdery mildew stem></a>
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      <li><a href=Snapdragon rust 3
  • Snapdragon rust 3

Powdery mildew

  • Powdery, fluffy white spots and blotches on leaves, stems, and flower parts
  • Tiny black round spheres may be visible within white spots late in the season
  • 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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  • Gray mold 1
  • Gray mold 2
  • Gray mold 3

Gray Mold
Botrytis cinerea

  • Irregular brown spots on leaves
  • Brown blossoms or petals; flowers drop off prematurely
  • Gray fuzzy mold develops on rotted tissue under humid conditions
  • Disease develops during cool, wet weather
  • More information on Gray Mold
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  • Downy mildew 1
  • Downy mildew 2
  • Downy mildew 2

Aster Yellows
Phytoplasma

  • Part or all of the leaves may turn yellow
  • Flowers fail to develop, remain small green and may be distorted
  • Clumps of weak shoots known as witches broom develop throughout the plant or on flower stalks
  • More information on Aster Yellows

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