Harmless to gardeners, hoverflies often cause panic because of their warning colouration of black and orange or yellow stripes, in various shades, mimicking wasps and bees. Well named, they hover above flowers during summer and are often present in huge numbers on pollen-rich flowers, especially if they’re yellow or orange. Adult females need to feed on nectar and pollen to get the protein needed to lay eggs. These eggs hatch into green or partially transparent maggots, that crawl around plants feeding on aphids. So hoverflies are good in two ways: the adults are pollinators and the larvae hoover up aphids for us.
How to help them Plant lots of yellow flowers such as layia, calendula and limnanthes among your aphid-prone plants, such as roses and broad beans. Even lilies will attract masses of hoverflies with their large, pollen-rich stamens.
The poached egg plant limnanthes will a ract hoverflies
Hoverflies are both pollinator and pest eater!