Mealybugs: how to spot and manage them

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Mealybugs are small, soft, sap-sucking insects wrapped in a white, cottony wax. They cluster in leaf joints and under leaves, and leave sticky honeydew behind.

How do I spot them?

1. White, fluffy, cotton-wool blobs tucked into leaf joints and along stems.
2. Sticky honeydew and black sooty mould on the leaves below.
3. Ants running up and down (they farm mealybugs for the honeydew).
4. Slowed, distorted growth.

Which plants do they target?

Growing any of these? See our guides to tomatoes.

Tomatoes, citrus, and many soft-leaved veg and herbs.

How do I manage them safely?

1. For small outbreaks, dab the clusters with a cotton bud dipped in diluted methylated spirits.
2. Spray insecticidal soap or neem oil, making sure to reach the hidden clusters.
3. Encourage ladybirds — the mealybug ladybird is a voracious predator.
4. Hose off and remove heavily infested growth, and discourage the ants.

For the bigger picture, see our guide to managing pests and problems safely.

Plan your patch: our free garden calendar shows what to plant now where you live. Ready to grow? Browse our raised garden beds or build your own with the garden bed builder.

Image: Whitney Cranshaw, Colorado State University, Bugwood.org, CC BY 3.0, via Wikimedia Commons.