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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Annuals and Perennials > Coleus > Discolored leaves

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Coleus > Leaves > Discolored leaves

1 of 4
  • Bacterial leaf blight 1
  • Bacterial leaf blight 2
  • Bacterial leaf blight 3

Downy Mildew
Plasmopara lamii

  • Large brown angular blotches may appear on leaves
  • Leaves may curl slightly downward, downy white to fungal growth on underside of leaves
  • Plants become yellow in color and stunted
  • Infected leaves prematurely drop from the plant leaving a barren stalk with few leaves
  • Cool, wet weather favors disease
  • More information on Downey mildew
2 of 4
  • Gray mold leaf 1
  • Gray mold leaf 2
  • Gray mold flowers 3

Root Rot
Rhizoctonia solani, Phytophthora spp., and Pythium spp.

3 of 4
  • Plant virus 1
  • Plant virus 2
  • Plant virus 2


  • Exposed parts of leaves bleach yellow to white
  • In severe cases, affected areas turn brown and brittle
  • Symptoms more severe in dry hot weather
  • For more information on Sunscald
4 of 4
  • Plant virus 1
  • Plant virus 2
  • Plant virus 2

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
  • For more information on INSV

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