Rose aphids

Roses can be spoiled by heavy infestations of sap sucking aphids (greenfly, blackfly and related insects) during spring and summer.

Rose aphids

Rose aphids

Quick facts

Common name Rose aphids
Latin name Several species, the most common is usually Macrosiphum rosae
Plants affected Wild and cultivated roses
Main symptoms Small green and/or pink insects clustered on the foliage, flower buds and shoot tips. Plants become sticky
Caused by Sap-sucking insects known as aphids or greenfly
Timing March-August

What are rose aphids?

Aphids, also known as greenfly and blackfly, are sap-sucking insects. There are several species that occur on roses in Britain.

 

Symptoms

Check your roses regularly for signs of infestation;

  • Green or pink aphids, cluster on the flower buds, shoot tips and young foliage
  • White cast aphid skins are often seen on infested flower buds and leaves
  • Flower buds and foliage covered in a sticky honeydew that aphids excrete
  • Black sooty moulds may grow on the honeydew

Control

Non chemical

  • Where feasible squashing aphids with finger can give good control
  • Aphids are eaten by various natural controls including ladybirds and their larvae, hoverfly larvae, lacewing larvae and are also killed by several species of parasitic wasps. Unfortunately these beneficial insects are often not present in sufficient numbers, particularly early in the season to prevent damaging aphid infestations developing.

Chemical

  • Look for aphids on the shoot tips and underside of leaves from spring onwards
  • Aphids that are exposed on stems and leaves can be controlled with organic sprays, such as natural pyrethrum (e.g. Bug Clear Gun for Fruit & Veg, Defenders Bug Killer, Ecofective Bug Killer (also contains fatty acids)), fatty acids (e.g. Solabiol Bug Free, Doff Greenfly & Blackfly Killer) or plant oils (e.g. Vitax Organic Pest & Disease Control, Origins Bug Control) can give good control of aphids. These pesticides have a very short persistence and so may require reapplication to keep aphid numbers in check
  • More persistent insecticides include the synthetic pyrethroids lambda-cyhalothrin (e.g. Westland Resolva Pest Killer), deltamethrin (e.g. Ultimate Fruit & Vegetable Pest Killer) and cypermethrin (e.g. Py Bug Killer) 
  • The systemic neonicotinoid insecticide acetamiprid (e.g. Bug Clear Ultra) can also be used
  • Plants in flower should not be sprayed due the danger to pollinating insects
  • Inclusion of a pesticide product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener

Download

Pesticides for gardeners (Adobe Acrobat pdf document outlining pesticides available to gardeners)

Biology

Aphids usually overwinter on roses as eggs laid on the stems in the previous autumn. However, in sheltered places there may be active nymphs and adults all year round.

Aphid numbers start to increase in spring when roses are producing new growth and reach a peak in early summer. Some rose aphids are green but a common species, Macrosiphum rosae, is pink. During spring and summer, the aphids are mostly wingless forms, 2-4mm long, that give birth to live young.

Winged forms develop when plants are heavily infested and aphids need to migrate to new host plants.


Gardeners' calendar

Advice from the RHS

Find out what to do this month with our gardeners' calendar

Advice from the RHS

Did you find the advice you needed?

RHS members can get exclusive individual advice from the RHS Gardening Advice team.

Join the RHS now

Get involved

We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.