Peony
Symptom Cause  
No flowers
Environmental Problems
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Shoots wilt and collapse; leaves spotted; flowers do not open.
Gray Mold (Botrytis Blight)
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Ants on stems and flower buds
Normal
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Weak flower stems
Poor Soil Conditions
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Leaves skeletonized; flowers damaged
Rose Chafers
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Leaves yellow, drop; bumps on leaves and stems; sometimes sticky leaves
Scale Insects
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Leaves discolored & distorted; black fecal spots on underside of leaf.
Thrips
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Weak flower stems
Too Much Shade
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