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

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Blueberry > Leaves > Spots, blotches or rings on leaves

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  • Image: Iron Chlorosis
  • Image: 2


  • Reddish-brown round to irregular spots on leaves
  • Berries become soft and wrinkled from the blossom end
  • 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
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  • Image: Honeycrisp Leaf Mottle Disorder 1
  • Image: Honeycrisp Leaf Mottle Disorder 2

Powdery Mildew
Microsphaeria alnia var. vacinii

  • Leaves may be reddish green, have red spots or red rings
  • Powdery white fungal growth may be seen in spots, covering the upper surface of the leaf, or not at all
  • Leaves may be cupped or distorted around infections
  • Infected leaves fall off prematurely
  • Often seen mid to late summer
  • More information on Powdery Mildew
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  • Image: Powdery Mildew 1
  • Image: Powdery Mildew 2

Botrytis Blight/Gray Mold
Botrytis cinerea

  • Leaves have brown, irregular lesions and may become distorted
  • Infected blossoms turn brown and become covered with a fuzzy gray mold
  • Berries are covered with a fuzzy gray mold
  • Twigs turn brownish-black and become gray
  • More information on Botrytis Blight/Gray Mold
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  • Image: Dogwood Borer 1
  • Image: Dogwood Borer 2

Mummy Berry
Monilinia vaccinii-corymbosi

  • In spring, new leaves turn brown along the veins and wilt
  • Young shoots bend into a shepherd's crook
  • Infected berries appear pinkish tan and feel rubbery
  • Berries eventually become whitish gray, shriveled, and drop off
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  • Image: Dogwood Borer 1
  • Image: Dogwood Borer 2

Ringspot Virus

  • Leaves may be mottled pale green and yellow, and distorted
  • Brown spots may be seen on leaves and stems
  • Plants have poor growth and yield
  • Plants eventually die, often after a hard winter
  • More information on Ringspot Virus

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