Epilachna beetles
Ladybird-like leaf-eating beetles and their spiny yellow larvae that scrape leaves into lace on beans, aubergine, potato and cucurbits.
Also known as: Mexican bean beetle, Spotted leaf beetle, Henosepilachna beetle
Symptoms and identification
Leaves are scraped from the underside into a skeleton of fine lacy veins, and then turn brown and dry. Orange-yellow or copper-coloured beetles with black spots and spiny yellow larvae feed on leaf undersides, and yellow egg clusters sit upright on the leaf.
Causes
Adults overwinter in leaf litter and plant debris and lay egg masses on the underside of leaves in spring and summer. Several generations develop in warm weather.
Organic treatment
Hand-pick beetles, larvae and yellow egg clusters and drop them in soapy water. Spray neem oil or insecticidal soap on larvae. Unlike true ladybirds, these beetles are pests, not helpers.
Prevention
Clear plant debris after harvest, check leaf undersides from early in the season, and cover young plants with mesh. Plant early to miss the peak of beetles.
Chemical treatment (use with care)
Use an insecticide labelled for beetles on that crop, following the label and harvest wait.