Spider Mites, Earwigs and Other Common Plant Visitors Explained
There is a tier of garden insect that bothers people every year and rarely deserves the alarm. Earwigs in the dahlias. Tiny things jumping when you brush the leaves. A bit of webbing on a stem. Most of it is harmless, some of it is helpful, and only one or two are genuinely worth treating.
Here is a guide to the smaller cast of common UK garden insects — what they are, what they actually do, and which ones to ignore.
The short version: Most small garden insects are harmless or beneficial. Red spider mite causes yellow leaf stippling in hot, dry, still spots and is worth treating with humidity and airflow if damage spreads. Earwigs eat aphids and small caterpillars and do more good than harm, despite occasionally chewing show flower petals. Leafhoppers, froghoppers and woodlice cause only cosmetic or no damage and rarely need action. Thrips cause silvery leaf streaking in hot summers but are usually cosmetic, worth treating only on prized plants with heavy damage.
Red spider mite
The "spider mite" name is misleading. They are tiny — about 0.5mm long — and not actually red until autumn, when they turn brick-coloured. In summer they are a pale yellow-green. The damage is usually visible first: a fine yellow or bronze stippling across the leaf, often with the dusty texture of a leaf sandpapered. Heavy infestations produce visible webbing on the leaf undersides.
Spider mites thrive in hot, dry, still positions. Plants against a south-facing wall in a courtyard are most at risk. The single most effective remedy is humidity — misting affected plants daily and improving airflow around them slows mite reproduction dramatically. Predatory mites (Phytoseiulus persimilis) are available for serious greenhouse infestations.
Worth treating: Yes, if damage is spreading. Spider mite populations explode in hot weather and an untreated infestation on a structural plant can disfigure it for a whole season.
Earwigs
Brown, flat, with the famous pincers at the back end. Active at night, hidden under stones and leaf litter during the day. Their reputation is worse than their behaviour. Earwigs eat aphids, mites and small caterpillars — they are a net benefit in most gardens. They do occasionally chew petals on clematis, dahlias and chrysanthemums, which annoys exhibitors but does not damage the plant.
If they are damaging show flowers, the traditional trap works: an upturned flowerpot stuffed with straw on top of a cane, placed near the plant. Earwigs shelter in it during the day and you tip them out somewhere else in the garden in the morning. No spraying needed.
Worth treating: No, in almost all cases. Earwigs do more good in the garden than harm. Trap and relocate from prized flowers if needed, but do not eradicate.
Leafhoppers and froghoppers
Small, narrow, often green or brown insects that jump suddenly when disturbed. They cause minor leaf speckling — sometimes a stippled silvery effect — but rarely enough to damage a plant. The "cuckoo spit" you see on plant stems in early summer is the foam shelter of froghopper nymphs underneath. Annoying, harmless, and easily washed off with a hose.
Worth treating: No. Hose off cuckoo spit if it bothers you. Leafhoppers themselves are not worth chasing.
Woodlice
Grey, segmented, often curling into a ball when touched. Woodlice feed almost entirely on decaying plant matter. They very occasionally nibble seedlings or soft fruit but are essentially harmless to established plants. Their presence usually means there is plenty of organic material — mulch, leaf litter, decaying wood — for them to recycle.
Worth treating: No. Leave alone.
Thrips
Tiny slender insects, often almost too small to see, usually black or brown. They feed on leaves and flowers and leave a silvery streaking with small black specks (their droppings) underneath. Common on privet, gladioli and roses in hot dry summers. Damage is largely cosmetic. A horticultural soap spray applied to the undersides of affected leaves brings populations down quickly if needed.
Worth treating: Only on prized specimens with visible heavy damage. Light infestations clear themselves with the next damp spell.
Related guides:
Frequently Asked Questions
Are earwigs beneficial to the garden?
Mostly yes. Earwigs eat aphids, mites and small caterpillars, and they recycle decaying plant matter. They occasionally chew petals on clematis, dahlias and chrysanthemums, which annoys exhibitors of show flowers, but they do not damage the plants themselves. On balance they do more good than harm in most gardens and are not worth eradicating.
What are the tiny bugs on my plants?
Identify them by where and how they appear. Tiny green or black insects clustered on new growth are aphids. Small white tufts in leaf joints are mealybug. Almost-invisible specks with yellow leaf stippling are spider mite. Small jumping insects with cuckoo-spit foam on stems are froghoppers. Tiny slender black insects with silvery leaf streaks are thrips. The first two are worth acting on; the rest rarely need treatment.
Should I worry about woodlice in my garden?
No. Woodlice feed on decaying organic matter and very occasionally nibble seedlings or soft fruit, but they cause no meaningful damage to established plants. Their presence usually just indicates plenty of mulch and leaf litter for them to break down, which benefits soil health.
A garden with healthy structural planting copes well with the everyday cast of insect visitors. Browse our Architectural Collections. Delivered free to your door.
