# Oleander aphid (Aphis nerii) > A small, bright yellow to orange sap-sucking aphid that forms dense colonies on oleander, milkweed and related plants and can weaken them by heavy feeding and honeydew production. Source: https://insectscanner.com/species/oleander-aphid/ (updated 2026-10-10) ## Is it dangerous? **Non-toxic.** Oleander aphids do not bite or sting people. Handling heavy infested plant parts can leave sticky honeydew on skin or clothing; wash off with soap and water. Although oleander plants are toxic, the aphids themselves are not a poisoning risk for people from casual contact. **Pets:** Aphids are not poisonous to pets through casual contact. However, pets chewing on heavily infested toxic plants such as oleander could be at risk from the plant's toxins; keep pets away from oleander foliage. ## Quick facts - Scientific name: Aphis nerii - Also called: Milkweed aphid - Order: Hemiptera (True bugs) - Family: Aphididae (Aphids) - Size: 1.5-3 mm body length - Colours: Bright yellow, Orange, Black (markings) - Habitat: On leaves, stems, buds and new shoots of oleander, milkweed, periwinkle and related plants; often in warm, sunny gardens and landscaping. - Range: Native to the Mediterranean region; now widespread (cosmopolitan) where host plants are cultivated, including North America, Europe, Africa, Asia, Australia and other regions. - Active: Active spring through autumn in temperate climates; year-round in warm regions. Mostly active during daylight but remain on plants continuously. - Lifespan: Individual adults live days to a few weeks; colonies persist through continuous reproduction. - Effect on plants: Sap-sucking pest - Pest: yes ## Overview Aphis nerii is a small, conspicuous aphid often seen in dense clusters on the new growth, flower buds and undersides of leaves of oleander, milkweed, periwinkle and other members of the Apocynaceae and related plant families. It feeds by sucking plant sap; heavy infestations can stunt growth, deform shoots and reduce flowering. Populations reproduce rapidly (many generations per year) by parthenogenesis in warm regions; no males or eggs are known, so all individuals are females that give birth to live young. The species has spread from its native Mediterranean region and is now cosmopolitan wherever host plants are grown. ## How to identify it Adults are 1.5-3 mm long, typically bright yellow to orange and quite plump-bodied. The head and thorax of winged forms are often darker (brown to black). Cornicles (the tubular rear projections typical of many aphids) are long and black. Legs and antennae are mostly black. Winged adults have a dark thorax and clear to slightly smoky wings; they are produced when colonies become crowded or when dispersal is needed. - Bright yellow to orange, plump aphids in dense clusters on young shoots, buds and undersides of leaves. - Long black cornicles and black legs contrast with the yellow body. - Presence on typical hosts: oleander, milkweed, periwinkle and related plants. - Winged adults darker on head/thorax with clear wings when present. ## Lookalikes - **Green peach aphid** (Myzus persicae): Usually green to yellow-green or pinkish with pale cornicles; commonly found on many vegetable crops rather than restricted to Apocynaceae hosts. - **Black bean aphid** (Aphis fabae): Often darker (green, red or black) with different host range and seasonally variable colours; not as consistently bright yellow-orange as Aphis nerii. ## Life cycle - **Egg (not known):** No egg stage is known for this species: no males have been found, and females give birth to live nymphs year-round where climate allows. - **Nymph (immature):** Nymphs resemble small adults and molt several times while remaining on the host plant; they begin feeding shortly after birth. - **Adult:** Adults are produced both wingless (apterous) and winged (alate). Wingless females give live young by parthenogenesis in many generations per year; winged adults disperse to new plants when colonies become crowded. ## Diet and predators - Young eat: Plant phloem sap from host plants (same as adults). - Adults eat: Plant phloem sap from oleander, milkweed and related species. - Predators of the young: Ladybird beetle larvae and adults, lacewing larvae, predatory hoverfly larvae, parasitic wasps. - Predators of adults: Same predators as juveniles; also ants may tend colonies for honeydew and can protect them from predators. ## Effect on plants and gardens Feeds on sap of oleander, milkweed, vinca/periwinkle and other Apocynaceae and similar plants. Heavy infestations cause leaf curl, yellowing, stunted growth, reduced flowering and sticky honeydew that can lead to sooty mold. ### How to get rid of it For small infestations, blast colonies off with a strong jet of water or prune and dispose of heavily infested shoots. Insecticidal soaps or horticultural oils smother aphids; repeat treatments may be needed. Encourage natural predators such as ladybirds, lacewings and hoverflies, and avoid excess nitrogen fertiliser that promotes soft new growth. On milkweed grown for monarch butterflies, avoid insecticides altogether and use water sprays or hand-squashing. Systemic insecticides are a last resort for ornamentals and must be used according to label instructions. ## Where and when to find it Look on new growth, leaf undersides, buds and young stems of oleander, milkweed, periwinkle and related plants. Winged forms may be seen on flowers and nearby plants when dispersing. - Best time: Spring through autumn in temperate zones; year-round in warm climates. Daytime inspections are fine because colonies remain on plants. - Tips: Check the undersides of leaves and inside bud clusters. Use a hand lens to see cornicles and body shape. Photograph whole colony for scale and some close-ups of individual aphids. ## Fun facts - Oleander aphids often sequester plant toxins from their host (milkweed/oleander), making them distasteful to some predators. - Dense colonies can produce copious honeydew that attracts ants; ants commonly farm and protect aphid colonies. - Because they multiply rapidly, a small number of aphids can become a large infestation within a week or two in warm weather. ## Frequently asked questions ### Do oleander aphids bite or sting? No. They are sap-sucking insects and do not bite or sting people. ### Are oleander aphids dangerous to people or pets? The aphids themselves are not toxic to touch. However, oleander plants are toxic if eaten by people or pets, so prevent pets from chewing infested oleander. ### Why are oleander aphids on my plant? They feed on plant sap and prefer tender new growth and flower buds. Warm weather and dense plantings encourage rapid population growth. ### How can I get rid of oleander aphids? For small infestations, blast colonies off with a strong jet of water or prune and dispose of heavily infested shoots. Use insecticidal soaps or horticultural oils to smother aphids; repeat treatments may be needed. Encourage natural predators (ladybirds, lacewings) and avoid excess nitrogen fertiliser that promotes soft new growth. For severe problems, systemic insecticides are effective but should be used as a last resort and according to label instructions. ### Will ants protect oleander aphids in my garden? Yes. Ants are attracted to the sugary honeydew and will often protect aphid colonies from predators in exchange for the honeydew. --- More about this species: [iNaturalist](https://www.inaturalist.org/taxa/71154), [Wikipedia](https://en.wikipedia.org/wiki/Aphis_nerii). Identify insects and spiders from a photo with the Insect Scanner iPhone app: https://apps.apple.com/app/id1543946563?pt=126685406&ct=web-markdown&mt=8 Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.