Aphids on oleander
Oleander is this aphid's principal host (UF/IFAS): bright yellow, black-legged colonies on the soft new shoots, sticky honeydew and black sooty mould on the leaves below, and sometimes deformed tips. UF/IFAS says numbers usually peak in spring but colonies can turn up all season. The damage is mainly cosmetic, though UF/IFAS notes repeated heavy infestations can stunt nursery plants. Water, fertilise and prune less, since all three push out the tender shoots it feeds on, and hose colonies off. Papery tan mummies mean the wild parasitoid Lysiphlebus testaceipes is already at work, so leave them. If colonies stay heavy, UF/IFAS lists insecticidal soap or oil; UC IPM says to cover the shoots thoroughly and not to spray drought-stressed plants or in very hot weather. Wear gloves when pruning: all parts of oleander are poisonous and the sap irritates skin.
At a glance
- Damage
- Bright yellow colonies on milkweed and oleander tips, honeydew, sooty mould
- Type
- Sap feeding · virus vector
- Settings
- Garden, Under glass
- Threshold
- None numeric — soap or oil only if colonies stay heavy
- Ally
- Cotesia congregata and other Braconidae
- Rate
- Wild — conserve; do not buy
How to confirm it
Bright yellow aphids with black legs, antennae, cornicles and tail, packed along milkweed or oleander stems, shoot tips and seed pods. The yellow body with black appendages is the combination UF/IFAS uses to describe this species.
Identification, lifecycle, degree days and every control option are on the full Oleander aphid profile. Not sure it is this pest? Answer four questions about the damage.