Insect & Disease ID And Diagnosis Guide: Deformities & Stunted Growth

Crinkling and distortion of young geranium leaves can result from aphid feeding.

Distortion of the leaf outline and white scarring result from thrips feeding on poinsettia.

Distortion and stunting of young growth results from thrips feeding on immature impatiens leaves.

Downward curling impatiens leaves and stunted new leaves indicate possible broad mite 
infestation.

Strapped, downward curled New Guinea impatiens leaves are a sign of broad mite feeding injury.

Stunted, distorted growth with yellowing and necrosis indicate downy mildew on argyranthemum.

Stunted, hardened, downward-curled leaves at the center of an African violet signal cyclamen mite infestation.

Stunted chlorotic growth on this primula indicates INSV.

Severe, strap-like leaf distortions on new leaves after pinching are thought to result from calcium or boron deficiency.

Puckered geranium leaves with injured, chlorotic margins indicate air pollution injury caused by a faulty boiler.

Light green, downward cupping, and distorted poinsettia leaves result from multiple nutrient deficiencies, usually caused by an inadequate fertilization program.

Pale brownish lumpy swellings at the base of argyranthemum indicate crown gall.

Blasted flower buds and cone-shaped leaves may signal boron deficiency or poor growing conditions — low light levels, high temperatures, and plant crowding.

Dead leaf areas caused by downy mildew can cause leaf twisting in coleus.

Chlorotic mottling and flower distortion and stunting in a zinnia due to TSWV.

Stunted and straplike new growth on this New Guinea impatiens may indicate cyclamen mite 
infestation.