Aphids are sap-sucking true bugs. They range in size from 1 to 7 mm (¼ in or less) long. Some aphids are known as greenfly or blackfly, but there are species that are yellow, pink, white or mottled. There are more than 500 aphid species in Britain. Some feed on only one or two plant species, but others can be found on a wide range of plant hosts. Many have lifecycles that involve more than one host plant. Almost any plant can be a host to aphids, including ornamentals, vegetables, fruits, greenhouse plants and houseplants. More information on aphids. 

Lupin aphid feeds on lupins (Lupinus).

A native plant is one that originated or arrived naturally in a particular place without human involvement. In the British Isles, native plants are those that were here during the last ice age or have arrived unaided since.

• Large, greyish-white aphids, up to 4 mm long, form dense colonies on the underside of leaves and on the flower spikes
• Sticky foliage covered with honeydew excreted by the aphids
• Heavily affected plants often wilt

Aphids form the basis of many food chains and it is not unusual to have some of these animals in a healthy balanced garden ecosystem. Unfortunately lupin aphid is unusual for an aphid as it often causes host plants to wilt. On established lupins aphids can be considered part of the biodiversity they support and should not cause long term harm to the plants, although alarming natural enemies will normally reduce numbers during late spring and into summer.

• Where possible tolerate populations of aphids
• Check lupins frequently from spring onwards so action can be taken before a damaging population has developed
• Use finger and thumb to squash aphid colonies where practical
• Encourage aphid predators in the garden, such as ladybirds, ground beetles, hoverflies, parasitoid wasps and earwigs. Be aware that in spring aphid populations often build up before natural enemies are active in sufficient numbers and then give good control

Lupin aphid is present on its host plants all year round.

Small numbers of aphids overwinter on the basal buds and they begin to reproduce in spring. For most of spring and summer the aphids are in the form of wingless females that give birth to live young. Aphid numbers generally peak when the plants are coming into flower.

When the aphids colonies become overcrowded in mid-summer, winged forms develop that can fly and colonise other lupins.