How to identify it
- Adults are about 1/16 inch long, milky white right after molting and soon dark brown, with dark-tipped wings that have a lighter band near the base.[1][2]
- Larvae are light or pale yellow with red eyes.[1][2]
- Flowers become deformed and discolored, and buds may be so injured that all blossoms are ruined.[1][2]
Where it lives
It occurs almost everywhere gladiolus is grown; it can't overwinter outdoors in northern North America, and its yearly spread probably comes from infested corms.[2]
Biology and life cycle
Females insert tiny, white, kidney-shaped eggs into leaves, flowers or corms.[1][2]
Two pale larval stages are followed by two pupal stages, the first with short wing pads and forward antennae, the second with longer wing pads and antennae folded back.[1][2]
Damage and signs
Health risk
Control
Sanitation
If corms are dug for winter storage, clean them gently and soak them for three hours in bleach at 4 teaspoons per gallon of water, then dry them thoroughly before storing.[1]
Pesticides
Several insecticides labeled for landscape use work as sprays; spray before flowers open to avoid harming pollinators.[1]
Common questions
- Why are my gladiolus flowers streaked and deformed?
- Gladiolus thrips feeding on buds and flowers can ruin the blossoms.[1][2]
- How do I keep thrips out of stored gladiolus corms?
- Clean the corms, soak them three hours in bleach at 4 teaspoons per gallon, and dry thoroughly.[1]
- When should gladiolus be sprayed for thrips?
- Before the flowers open, to protect pollinators.[1]
Sources
- NC State Extension, “Gladiolus Thrips.” content.ces.ncsu.edu/gladiolus-thrips (accessed 2026-10-15)
- University of Florida IFAS Extension (Featured Creatures), “Gladiolus Thrips, Thrips simplex (EENY-036).” ask.ifas.ufl.edu/publication/IN163 (accessed 2026-10-15)
- iNaturalist, “Thrips simplex taxon page (order and family).” www.inaturalist.org/taxa/308542 (accessed 2026-10-06)