Zinnia
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Holes chewed in leaves and flowers
Japanese Beetles
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Skinny; spindly seedlings
Lack of Light
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Pale spots on foliage
Leafhoppers
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Leaves stippled, yellowing or bronze; dry out and drop may be webbing visible; sometimes galls form on leaves
Mite
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White powder coats top of leaves
Powdery Mildew
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Black powdery sooty mold fungus forms on honeydew; plants may die if problem continues
Sooty Mold
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Leaves and roots chewed
Various Beetles
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