Chive
Symptom Cause  
Soft, brown tissue at neck
Botrytis
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Young plant falls over at soil line and dies
Damping-Off
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Pale green, yellow spots on leaves, fuzzy purple cover spots
Downy Mildew
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Leaf tips wilt, bulb is soft and brown inside
Fusarium Basal Rot
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Tops wilted, stunted; growth slows, roots turn pink; leaves yellow or whiten, die
Pink Rot
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