Thrips damage on houseplants appears as silvery, bronze, or grey streaks and patches on the leaf surface, caused by the insects piercing individual plant cells and sucking out their contents. The damaged cells collapse and the area takes on a bleached, metallic, or papery appearance. Small dark specks (thrips frass) are typically visible alongside the silver streaking. On flowers, thrips cause discolouration, distortion, and premature petal drop. Badly infested leaves may curl, become stunted, or show significant distortion on new growth, because thrips often feed on developing leaf tissue inside buds, distorting the leaf as it expands.
Where to Find Thrips on Plants
Thrips are tiny (1 to 2 mm), slender insects, usually pale yellow-white as nymphs and dark brown or black as adults. They are fast-moving and quickly flee to hide when disturbed, making visual inspection difficult. The most reliable way to detect them is to hold a piece of white paper under the affected leaves and tap or shake the plant briskly: adult and nymph thrips fall onto the paper and are visible against the white background as tiny moving specks.
Check the undersides of leaves, the inside of flower buds, and deep in leaf rolls. Thrips prefer to feed in sheltered areas, particularly on new growth, flower buds, and the growing tips of plants. The characteristic silver stippling damage is usually the first sign noticed before the insects themselves are seen.
Distinguishing Thrips Damage from Spider Mite Damage
Both thrips and spider mites cause silvery stippling on leaves, but the damage patterns differ. Spider mite damage tends to be more uniform stippling across the leaf surface, often with fine webbing visible between leaves in heavier infestations. Thrips damage tends to appear in streaks and irregular patches aligned with the direction of feeding, and is often accompanied by visible black frass specks. Thrips also specifically distort new growth and flowers; spider mites rarely cause the same degree of growth distortion. See our guide on spider mite treatment for comparison.
How to Treat Thrips
Thrips are persistent pests that require consistent treatment over several weeks because their eggs are laid inside plant tissue and protected from contact sprays. The most effective approach combines several methods. Yellow or blue sticky traps placed near the plant catch adult thrips and monitor whether numbers are declining. Neem oil or spinosad-based insecticide sprays applied thoroughly to all leaf surfaces, undersides, and growing tips kill active nymphs and adults. Spinosad is particularly effective against thrips.
Apply treatment every five to seven days for at least four to six weeks to break the breeding cycle. Eggs hatch approximately a week to ten days after being laid, so gaps in treatment allow new cohorts to establish. Remove any heavily damaged leaves and all flowers, as thrips often concentrate in flowers and these are difficult to treat. Quarantine the affected plant to prevent spread to others in your collection. See our guide on quarantining plants with pests.
Why Thrips Infestations Recur
Thrips are one of the more challenging pests to fully eradicate because the egg stage is hidden inside plant tissue and protected from all contact insecticides. Adults can also reinfest from outdoors through open windows in summer, when thrips populations in the garden are high. If your indoor plants are repeatedly infested during summer, keeping windows closed or screened in warm weather, and treating any garden plants nearby, reduces the source of reinfestation. See our guide on why pests keep recurring for the broader pattern of reinfestation.
Related Questions Worth Knowing
My plant's new leaves are coming in distorted and small. Could that be thrips? Yes. Thrips feeding on developing tissue inside buds before leaves open is one of the most common causes of leaf distortion in houseplants. The leaf expands around the damage, producing crinkled, puckered, or stunted new growth. This is particularly common on plants with tightly furled new leaves like Marantas and Calatheas. Check these plants carefully by unrolling a new leaf and looking for thrips nymphs inside. See our guide on identifying common houseplant pests.
How long does it take to get rid of thrips? With consistent treatment applied every five to seven days, most thrips infestations are under control within four to six weeks. Complete eradication can take longer because new adults may reinfest from outside. Monitoring with sticky traps allows you to track whether the population is declining. A sustained reduction in trapped adults over two to three weeks indicates the treatment is working.
Will thrips damage be visible permanently? Yes. Leaves that have been damaged by thrips retain their silver streaking permanently; the damaged cells do not recover. The improvement will be visible on new leaves grown after the infestation is controlled, which will emerge undamaged. Remove heavily damaged leaves if their appearance is significantly affecting the plant's look, but prioritise treating the infestation first.