Organic treatment
- Isolate the plant immediately — thrips move readily between neighboring pots.
- Prune the most damaged leaves to remove larvae hiding in curled tissue.
- Hang blue sticky traps to monitor and reduce the flying adult population.
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Sap-sucker
Thrips
Silvery streaks and distorted new leaves; black specks (frass) nearby.
Severity
Identification
Thrips are slender, fast-moving insects only a couple millimeters long. Damage shows as silvery, papery patches on leaves with tiny black frass (droppings) scattered across the scarring. New growth often emerges twisted or stunted.
Life cycle & spread
Adults lay eggs inside leaf tissue; larvae drop to the soil to pupate before emerging as adults, which makes soil drenches useful alongside foliar treatment. A generation completes in 1–3 weeks depending on temperature.
Chemical treatment
- Alternate a systemic granule (taken up through the roots) with a contact spray for 4–6 weeks to break the life cycle.
- Treat soil and foliage together — thrips pupate below the surface.
Prevention
- Screen windows in growing season; thrips commonly blow in from outdoor plants.
- Inspect new nursery stock closely before bringing it inside.
- Avoid over-fertilizing with nitrogen, which produces the soft new growth thrips prefer.
Commonly affects