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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Fruit > Blueberry > Spots or blotches on stems or branches

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Blueberry > Stems/branches > Spots or blotches on stems or branches

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  • Image: Iron Chlorosis
  • Image: 2

Canker diseases
Fusicoccum putrefaciens and Phomopsis vaccinii

  • Reddish brown, target like cankers can be found on infected branches
  • Cankers are often low on the branch and near a leaf scar
  • Cankers enlarge each year until they girdle and kill the stem
  • In summer, leaves on infected branches, wilt and turn reddish brown
  • Small black bumps can be found around cankers and on dead branches
  • More information on Canker diseases
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  • Image: Iron Chlorosis
  • Image: 2


  • Salmon to orange colored sticky spore masses develop on infected berries and stems when wet
  • Infected twigs/canes have dark brown lesions with raised bumps arranged in concentric circles
  • Reddish-brown round to irregular spots on leaves
  • Berries become soft and wrinkled from the blossom end
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  • Image: Powdery Mildew 1
  • Image: Powdery Mildew 2

Botrytis Blight/Gray Mold
Botrytis cinerea

  • Twigs turn brownish-black and become gray
  • Infected blossoms turn brown and become covered with a fuzzy gray mold
  • Berries are covered with a fuzzy gray mold
  • Leaves have brown, irregular lesions and may become distorted
  • More information on Botrytis Blight/Gray Mold

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