Cosmos Problems
Symptom	Probable Cause
Leaves Wrinkled or Curled; Discolored, Stunted, Tend to fall off	Aphids
Weak Growth, Leaves Stunted, Yellowing, Brown Tips; Bulbs or Roots Damaged	Root Aphids
Leaves Riddled With Shotholes; Caterpillar inside Stalk	European Corn Borer
Pale Spots On Foliage	Six-Spotted Leafhopper
Flowers and Seeds Damaged	Caterpillar of Sunflower Moths
Leaves Stippled, Yellowing Or Bronze; Dry Out And Drop May Be Webbing Visible; Sometimes Galls Form On Leaves	Spider Mites
Flowers Yellow-green; Deformed; Shoots Spindly	Aster Yellows, a bacterial disease; replace the plant
Sudden Wilting; Stems Rot At Soil Line	Bacterial Wilt, a bacterial disease; replace the plant
Green Plant Colors, Wilts, Tans; Pink Mass on Roots; Plant Dies	Fusarium Wilt, a fungal disease
White Powder Coats Top of Leaves	Powdery Mildew, a fungal disease
Leaves Yellow, Wilt, Die	Root Rot, replace the plant
Black Decay on Stems, Spreads, Brown-Black Lesions Form	Stem Canker; replace the plant
Dark Lesions on Stems; Roots Rot	Stem Rot; replace the plant
Attacks Stems at or Below Ground Level; Plant Wilts, Yellows, Decays	Southern Blight, a fungal disease
Plant Actually Disappears	Deer