In the wild: Wild roses
In the garden: Cultivated roses
Throughout UK and Europe
There are a number of different rose aphid species, although Macrosiphum rosae is the most common. They are green and/or pinkish red in colour, have long legs with distinctive black knees and are often found clustered in large numbers around rose flower buds, young stems, shoots and under new leaves. Both non-winged and winged aphids are usually present within an infestation.
Rose aphids will damage plants by sucking out sap and weakening the shoots and flower buds. Flowers may open deformed. Honeydew will attract sooty moulds and ants.
Check plants often for early outbreaks. Either squash the aphids or remove, contain and destroy the parts of the plants where they are present. Encourage beneficial insects including ladybirds, hoverflies, and lacewings, which are important aphid predators.
In small outbreaks, a high-pressure spray from the garden hose can help remove aphids from plants. Where aphid problems persist, as a last resort organic pyrethrum-based pesticides are available from garden centres. These need to be applied following the instructions on the label.
Ladybirds and their larvae are very effective predators of aphids and should be welcomed into your garden. Other predators such as hoverfly larvae and lacewings also provide effective natural ways of controlling aphids. Parasitic wasps will help to control aphid infestations by injecting aphids with their eggs. The eggs hatch into maggots that eat the aphids from the inside out. Eventually the wasp maggots kill the aphids, turning them into ‘mummies’ before emerging from the mummified bodies as adult wasps. Ants will often farm aphids and collect the sugary honeydew that aphids produce. The ants protect aphids from predators and can move them to new plants to establish new aphid colonies.