What are aphids and what damage do they cause?

Aphids are a group of sap-sucking insects that feed by piercing plant tissue of leaves, flowers, buds and fruit stems. Damage can cause galls in leaves and stems, distortion of leaves and flowers and death of shoots. Aphids are sap sucking insect pests that feed by piercing plant tissue of leaves, flowers, buds and fruit stems. Many aphids are found on the underside of leaves or on the growth tips of leaves and buds, particularly new growth that has not fully expanded and will appear deformed or stunted. Aphids feeding on fully expanded leaves may cause the leaf to become chlorotic (yellow), wilt and fall from the plant.

They leave sticky secretions that often attract ants and can lead to a fungal disease called sooty mould that is not only unsightly but can compromise photosynthesis and yields of fruit and flowers if they are contaminated. Aphids can reproduce rapidly meaning infestations can seem to appear out of nowhere.

Aphids are commonly found on: Ornamentals such as roses, gardenia and oleander; vegetables such as cabbage and tomato; fruit such as peach, nectarines, cherries and apples.

Natures solution:

Nature has a built-in defense mechanism to help bring pests like aphids under control. When pests move in and the population increases, beneficial bugs that feed on aphids will also arrive. Beneficial bugs will target your aphids without doing any damage to your plants or other animals. The larvae of some of these aphid predators can eat up to 60 aphids a day! However, the larvae may look less familiar. This is why caution should be used applying broad spectrum pesticides that don’t discriminate between the good guys and the baddies.

Aphid predators:

Lacewings

Lacewings are general predators, but aphids are one of their favourite foods. As a bonus Lacewings will also target scale, mealybugs and psyllids.

Larvae carry their prey on their back then suck out their innards.

Keep your eyes peeled for their eggs throughout Spring and Autumn. They are quite distinctive hanging from the end of a very fine stem.

Hoverflies

Hoverflies look like bees but have only one set of wings and no stinger. They are the second most important pollinator next to bees and eat aphids – very underrated bugs.

Ladybirds

Larvae are dependent on aphids and other soft-bodied prey as a food source.

Adults also consume aphids but have a more diverse diet that includes nectar and pollen.

Parasitic Wasps

Some parasitic wasps are excellent scouts and will find aphids by the smell of the honeydew secretions, getting to work before you even become aware of the problem.

Talk about gruesome…
The female wasp lays its egg inside the aphid’s body. Once the maggot hatches it will eat the aphid alive, from the inside out! It then uses the aphid corpse as a cocoon before emerging as an adult. Mummified aphids can be easily distinguished by the brown colour and desiccated, shell-like appearance.