Broad mites
Microscopic mites that cause twisted, hardened, bronzed leaves and stunted growth on peppers, aubergines and many ornamentals.
Also known as: Polyphagotarsonemus latus, Yellow tea mites
Symptoms and identification
New leaves are small, thick, brittle and twisted or cupped downwards, with a glossy or bronzed look. Growth tips stop, buds and flowers drop or are distorted, and fruit become rough and scarred. You cannot see the mites without a strong lens, and damage looks like a virus or herbicide injury.
Causes
Broad mites favour warm, humid conditions and spread on air currents, tools, hands and infested plants brought in. They are common on indoor and greenhouse plants and in warm climates outdoors.
Organic treatment
Remove and bin badly affected growth. Spray horticultural oil, neem oil or insecticidal soap on new growth and leaf undersides weekly for several weeks. Predatory mites can help control them in greenhouses.
Prevention
Inspect new plants before bringing them in, keep susceptible plants apart from infested ones and use clean tools. Control weeds around the garden.
Chemical treatment (use with care)
Use a miticide labelled for broad mites on that crop, following the label, as ordinary insecticides do not control mites.