Thrips on houseplants
Indoors it is a flower feeder first: the RHS names African violet, streptocarpus, cyclamen, fuchsia and pelargonium among its hosts, and UC IPM notes feeding can make African violet blooms age early. Check the flowers of any new plant for thrips or pale flecking before buying; the RHS suggests blue sticky cards to monitor and reduce numbers.
At a glance
- Damage
- Silvered scars, black frass specks, flecked petals
- Type
- Sap feeding · virus vector
- Settings
- Under glass, Field, Garden, Indoors
- Threshold
- Pale flecks on petals or leaves, with black specks
- Release
- Amblyseius cucumeris
- Rate
- 10–50 per plant, weekly
How to confirm it
Tap flowers or shoot tips over white paper: slender insects under 2 mm that run rather than jump. Look for black varnish-like specks in the silvered patches. Naming the species for certain takes an expert with a microscope.
Identification, lifecycle, degree days and every control option are on the full Western flower thrips profile. Not sure it is this pest? Answer four questions about the damage.
Work it out
How many do I need?
Carries Amblyseius cucumeris and houseplants through so nothing is re-entered. Open the calculator →