Garlic
Symptom Cause  
Soft brown tissue at neck
Botrytis
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Cloves small
Compacted Soil
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Sunken spots on leaves; later, a purplish mold develops over spots
Downy Mildew
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Stunted plants, yellow leaves
Nematodes
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Roots turn pinkish or red, eventually rot; plant is stunted with wilted tops
Pink Rot
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First starts on top or sides of the bulb where disease or injury has caused an opening in the skin. The fungus develops between dry, dead outside of bulbs and the first inside of the bulb skin. Initially become water soaked looking spots. Under dry conditions diseased bulb parts dry and shrivel, and black spots are visible on the outside.
Smut (fungus)
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White growth at neck, older leaves turn yellow and die, the plant is stunted, and later all foliage falls off
White Rot
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