What's eating my oleander?

Oleander is chewed by the oleander aphid (bright yellow, hard to miss) and the oleander caterpillar in warmer climates. Scale insects colonise stems. Despite its toxicity, these specialist pests are well adapted to its alkaloids. In the UK and cooler US zones, aphids dominate; in the South and California, caterpillars cause rapid defoliation.

Dense colonies of vivid yellow aphids on shoot tips; sticky honeydew; sooty mould blackening leaves Knock off with water; insecticidal soap or neem oil; introduce ladybirds; avoid excess nitrogen fertiliser that promotes soft growth

Leaves stripped to bare midribs, starting at shoot tips; masses of orange caterpillars with black tufts Hand-pick and dispose of bags in sealed rubbish; Bacillus thuringiensis (Bt) spray on young caterpillars; pyrethrin for heavy infestations

Brown or white waxy bumps on stems; yellow leaf spotting; weakened, stunted growth Scrub off with a soft brush and rubbing alcohol; horticultural oil spray in late winter when dormant