Two-spotted spider mite
Tetranychus urticae
Microscopic sap-suckers that flourish in hot dry weather, causing leaves to bronze and dehydrate. Fine webbing gives them away.
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Identify from a photoBackground
Two-spotted mite is a worldwide pest of many vegetable and ornamental crops. Individuals are only around 0.5mm across, so damage is often noticed before the mites are. Feeding removes chlorophyll from leaf cells, producing stippled, bronzed, dehydrated-looking foliage. Under severe pressure the plant is smothered in fine silk webbing.
Dry, dusty, hot conditions favour rapid population growth and also stress the natural enemies. Wet misty weather and predatory mite populations are the main brakes on outbreaks.
How to identify
- Adults: 0.5mm, straw-yellow to green with a dark spot on each side of the body
- Eggs: round, translucent, on leaf undersides
- Damage: fine stippling on upper leaf surface, progressing to bronze and grey, fine webbing on leaf undersides and growing tips
Life cycle
Egg to adult in 7-10 days at 25-30C. Females lay up to 100 eggs in their 2-4 week life. Populations can double in under 3 days in hot dry weather.
Weather triggers
- Temperature: 15-40°C
- Humidity: >40%
- Thrive in hot dry weather (>28C with low humidity). Cool wet conditions suppress them.
Peak season (southern hemisphere)
Red = active season · Dark red outlined = this month
Affected vegetables & crops
Click any crop to see current prices and growing info.
Climate zones at risk
Organic & low-impact control
- Regular overhead watering or hosing of leaf undersides disrupts them
- Horticultural oil or wettable sulphur sprays (not in high heat)
- Release of predatory mite Phytoseiulus persimilis for persistent infestations
- Remove heavily webbed leaves
Chemical control
- Resistance to many miticides is widespread. Rotate active ingredients if used
- Bifenazate and etoxazole are softer options for commercial use; home gardeners should rely on oils, sulphur and predators
Always read product labels. Registrations change.
Prevention
- Avoid extended dry stress. Irrigate evenly
- Wash dust off foliage regularly
- Do not use broad-spectrum insecticides that kill the predatory mites
Companion planting
No specific plant reliably deters two-spotted mite. Diverse planting that supports natural predators is the stronger approach.
Biosecurity
Cosmopolitan pest. No quarantine concerns.
Know when Two-spotted spider mite is actually about
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