How to Get Rid of Aphids on Roses: A Complete Guide

Aphids are one of the most common and destructive pests that can infest rose bushes. These tiny insects suck sap from the leaves, buds, and stems of roses, damaging plants and deforming growth. Left uncontrolled, aphids can quickly spread and kill an entire rose bush. Fortunately, there are many effective methods for getting rid of aphids and protecting your roses. This comprehensive guide will provide tips and solutions for eliminating aphids and keeping them away for good.

What are Aphids?

Aphids are very small, soft-bodied insects that feed by sucking sap from plant tissue. They come in a variety of colors like green, pink, white, grey and black. Aphids have piercing-sucking mouthparts that are used to pierce plant tissue and extract sap. They often feed in large groups, causing curled, yellowed or distorted leaves and stunted plant growth. Aphids secrete a sticky waste called honeydew which often attracts ants and leads to the growth of sooty mold fungi. Over time, heavy aphid infestations can kill plants.

There are thousands of species of aphids, many being host specific to certain plants. The most common aphids that infest roses are the rose aphid (Macrosiphum rosae), the potato aphid (Macrosiphum euphorbiae) and the green peach aphid (Myzus persicae). These aphids can be light green, pink, red, brown or black in color.

Signs of Aphids on Roses

It’s important to regularly check your rose bushes for early signs of aphid activity so you can take action before major damage occurs. Here are some telltale signs that aphids may be present:

• Curled, yellowed or distorted leaves Aphids inject toxic saliva into plants during feeding which causes leaves to become misshapen and discolored

• Sticky residue on leaves or stems: This “honeydew” is the sugary waste product excreted by aphids. It’s a food source for sooty mold fungi which leaves black residue.

• Ants on plants: Ants are often attracted to the honeydew secreted by aphids. Seeing lots of ants can indicate an aphid problem.

• White molted skins Aphids shed their exoskeletons as they grow. Look for white leftover skins on leaves as evidence of aphids

• Aphid colonies on stems or undersides of leaves: Check carefully along stems and the undersides of leaves for clusters of actual aphids. They may be green, pink, black or other colors.

Why Get Rid of Aphids?

Although a few aphids won’t do much damage, large uncontrolled populations can seriously impact the health and appearance of rose bushes. Here’s why it’s important to control aphid infestations:

• Plant Damage: Aphids suck nutrients and sap from roses as they feed, weakening and stunting plant growth. New shoots and buds may be deformed.

• Spread of Disease: Aphids can transmit viral plant diseases like rose mosaic from plant to plant as they feed.

• Sooty Mold: The honeydew secreted by aphids allows growth of unattractive black sooty mold on leaves and stems.

• Death of Plants: Heavy, uncontrolled aphid feeding can kill rose buds and entire plants.

• Spread to Other Plants: Aphids often spread from plant to plant. Getting rid of them on roses can prevent infestation of other plants.

Effective Methods to Get Rid of Aphids on Roses

If you suspect aphids on your roses, taking quick action is important. Here are some of the most effective methods recommended for getting rid of rose aphids:

Remove Aphids Manually

For light infestations confined to just a few leaves, manually removing aphids can eliminate the problem. Take a damp paper towel and wipe aphids off of leaves, stems and buds. Make sure to check the undersides of leaves where aphids often hide. Be sure to crush any aphids you remove to prevent them from spreading. Discard waste in a sealed plastic bag.

Use Insecticidal Soap

Insecticidal soaps made from potassium salts of fatty acids are an effective organic treatment for killing aphids. Spray insecticidal soap liberally on the undersides of leaves, stems, buds and the entire rose bush. Two or more applications a week apart may be needed to kill newly hatched nymphs. Avoid applying soap during the hot midday sun.

Apply Horticultural Oil

Horticultural oils smother overwintering aphid eggs and adults. For best results, apply dormant oil in early spring before rose buds open fully. Be sure to coat the undersides of leaves and stems thoroughly. Horticultural oil can also deter aphid reinfestation during summer if applied to infested plants.

Use Neem Oil

Neem oil comes from the seeds of the neem tree. It’s a natural insecticide that disrupts the growth and reproduction of aphids. Mix neem oil with water according to label directions and spray on roses, especially new growth. Reapply every 7 to 14 days to deter aphid populations. Neem oil also repels other rose pests like Japanese beetles.

Apply Insecticidal Dust

Diatomaceous earth is a natural mineral dust that abrades the waxy covering on insect bodies, causing dehydration and death. Gently dust leaves, stems and buds of roses to control aphid populations. Reapply after rain or heavy watering. Use a mask to avoid inhaling fine dust particles.

Use Pyrethrin Insecticide

Pyrethrin insecticides are made from natural pyrethrum extracted from chrysanthemum flowers. Pyrethrin quickly paralyzes and kills insects on contact. Spray pyrethrin on roses according to label directions to control heavy aphid infestations. Reapply every 5 to 7 days for full control. Pyrethrin can harm beneficial insects – use selectively.

Employ Natural Predators

Encouraging natural aphid predators like ladybugs, lacewings, hoverflies and birds can help reduce aphid numbers. Avoid pesticides that could kill these beneficials. Plant pollen and nectar flowers to attract predators to your garden. You can also purchase ladybugs to release near infested roses.

Prune Heavily Infested Areas

If aphids are concentrated on a few shoots or canes of the rose bush, simply prune those parts off. Remove the infested portions and discard (do not compost). This can eliminate the worst aphids and give the plant a fresh start. Be careful not to prune too much or you risk killing the bush.

Preventing Aphids on Roses

Once you’ve succeeded in getting rid of aphids on your roses, there are some important things you can do to help keep them from coming back or spreading:

• Check rose bushes very frequently – at least once a week if possible – for early signs of aphids like honeydew or curled leaves. The sooner you catch an infestation, the easier it will be to treat.

• Use row covers on rose bushes in spring to form a physical barrier against early aphid activity. Remove covers if temperatures exceed 85°F.

• Prune roses lightly in late winter to remove old wood and promote vigorous new growth that’s less vulnerable to pests. Avoid heavy pruning which stimulates excessive vulnerable new growth.

• Fertilize roses sparingly to avoid creating the fast, tender new growth that attracts aphids. Use slow-release organic fertilizers.

• Remove weeds from the rose bed and surrounding areas. Many weeds serve as secondary hosts for aphids.

• Consider spraying approved insecticides on roses as a preventive measure before aphid populations build up in spring. Neem oil is a good organic choice.

Aphids are a very common and destructive pest of roses, capable of deforming growth, spreading disease and eventually killing plants if left uncontrolled. Carefully monitoring for early aphid activity and taking prompt action at the first signs of infestation is key. Both organic and traditional insecticide products are effective options, along with manual removal, natural predators and pruning. Preventive measures like row covers and early sprays can also help reduce aphid problems and keep your roses vigorously growing and blooming.