Vinca
Symptom Cause  
Leaves wrinkle/curl/discolor/stunt, die
Aphids
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Leaves discolored; distorted
Aster Leafhoppers
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Shoots blacken and die back to ground
Canker (fungus)
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Shoots blacken and die back to ground
Dieback (fungus)
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Foliage looks burned
Dog Urine
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White, cottony masses, leaves speckled; sooty mold fungus may form on leaves - may kill plant
Mealybugs
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Leaves and branches encrusted with small bumps; stunted plant growth
Scale Insects
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