Marigold
Symptom Cause  
Leaves wrinkled or curled; discolored, stunted, tend to fall off
Aphids
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Flowers yellow-green; deformed; shoots spindly
Aster Yellows
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Holes in leaves; chewed edges
Caterpillars
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Plant actually disappears
Deer
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Plants stunted and yellow
Fusarium Wilt
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Gray spots on leaves
Gray Mold (Botrytis Blight)
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Holes in leaves and flowers
Japanese Beetles
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Black spots with spore bodies on leaves
Leaf Spot
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Leaves discolored; distorted
Leafhoppers
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Leaves stippled/yellow/bronze/dry out/Drop. Webbing visible; leaf galls
Mite
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Leaves discolored and distorted; plants stunted
Mosaic Viruses
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Few blossoms; excessive foliage,including yellowing and wilting of lower plant leaves; browning of leaf margins and tips; black, brown or rotting roots; slow to no growth; sudden death of seedlings; and leaf drop.
Over Fertilized
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Deformed or dwarfed flowers
Plant Bugs
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Black powdery sooty mold fungus forms on honeydew; plants may die
Sooty Mold
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Dark lesions on stems; roots rot
Stem Rot
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No blooms; faded blooms
Weather Conditions
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