Rose Pests: Identify And Deal With Them

When we say “Rose Pests,” we’re not necessarily talking about those pesky visitors like your husband, kids, or the neighbors dog who come trapsing up the path to interrupt right when you’re deep in the middle of your garden, basking in the sanctuary of blossoms.

No, what we’re really referring to are those little bitty black bugs that mar your treasured blooms or the funny looking crust that showed up a couple weeks ago. Some of these rose pests are no more than an annoyance, while others can literally kill your plant. So it’s a good thing to be able identify and handle these rose pests when they’re encountered. Most pests require only an insecticide spray to handle, so if caught early, you should have no trouble controlling and even eradicating these little invaders. On the other hand, we would also like to find you some organic solutions as it’s good to think about the environment. We’ll add those as we can.

So use the list below to determine which rose pest you’re dealing with and how to handle it.

Aphids

Aphids

It’s great that aphids are easy to control, otherwise they might be more formidable rose pests for the gardener. These little green/brown insects swarm (colonize) over plants, sucking the sap from them. They are 1/8-inch long and are also known as plant lice. In addition to green or brown, they can also be red or black. Mostly seen in spring or early summer, they damage new shoots by attacking them in large numbers. They can stunt or slow plant growth and deform leaves.

Ladybugs (or ladybirds) are an aphid’s natural predator, helping to keep these rose pests populations under control. Also, a dish soap and water solution is effective in ridding them from your roses.

Read More About Control of Aphids

Beetle Family

Read more on how to control the various common beetles this summer. Including Fullers, Metallic Flea beetle, Japanese and Spotted Cumcumber beetles. Most of these can be controlled with natural or organic methods, although insecticides are also viable methods if you wish to use chemicals.

Caterpillars

Caterpillar

Caterpillars skeletonize leaves or chew holes in them and also bore through buds. They will launch a fine thread and drop off a plant if disturbed. All varieties of these rose pests can be controlled with insecticide. Recommened treatment is to use Neem Oil, which is probably the best natural treatment available for a range of beetles, caterpillars and even fungla diseases. 

See our page on beetle control for more information on using Neem Oil.

Leaf Rollers

In spring, these little guys roll up foliage and start chewing, boring their way through leaf and bud. Use an insecticide or Neem oil.

Midge

Notice a sudden blackening of buds or young shoots on your roses? It could be the midge, a minute maggot about 1/25 of an inch long that rasps the tender tips of new growth, causing them to blacken and shrivel. Since the larva pupate in the soil, that is where you should begin to control the Midge.

Nematodes

The name nematode may sound kind of cute, but these tiny animals cause swellings on your roots and stunt growth. They will also cause pale green leaves and wilting in mild weather. You’re going to need an all-purpose rose spray for these fellows. Make sure the label mentions nematodes to ensure its ability to handle this kind of infestation.

Rose Slugs

Rose Slug

 

This insect is actually a fly in its larval stage. It is yellowish green and eats holes in leaves. Over time it will skeletonize them. You’ll need an insecticide to take of the rose slug. But quite honestly, there is no need to do anything about them unless you have a bad infestation.

Scales

Rose Scale

If you find a crusty white or gray shell sucking sap from your plants, you’ve got Rose Scale. They’re primarily found along stems and branches, but can spread to the stalks of your flowers. By the time that happens, though, your plant would be stunted and spindly with a white, flaky crust on its bark. You’ll want to cut out infested areas and apply a dormant lime sulfur spray in early spring. Also, use an insecticide.

Cottony Cushion Scale

This pest doesn’t cause much damage per se, but it does produce a sugary-sticky substance called honeydew, which can lead to sooty mould. It infests branches and twigs and is oval-shaped, reddish-brown and has black hairs. The female body encases hundreds of red eggs. Handle this pest with insecticide.

California Red Scale

Less than 1.5 mm across, orange to orange-pink in color, this scale appears frequently in plague numbers. It causes yellowing, leaf fall as well as twig and branch dieback as it infests upper surfaces of foliage. May cause plant death if seriously infested. Use insecticide to control.

Spider Mites

Spider Mite

If you find silvering or dry-looking leaves; if foliage is a dull red or yellow color, you may have spider mites. You may find fine webbing underneath, which is a sure sign of Spider Mites (aka Two Spotted Mites or Red Spider Mites). Sucking the life from the undersides of leaves, they leave their eggs and webbing behind. Eventually, defoliation can result.

It’s a good thing these tiny creatures hate water, so hosing or misting your plants frequently will go a long way towards controlling them. If needed, use a rose miticide every three days to curb re-infestation by hatching eggs.

Thrips

Thrips

Tiny squirming insects with wings slither between petals to suck juices from the buds of plants, making them appear bruised. Thrips can be nearly invisible, favor white and pastel roses and resemble fine black slivers of wood. You’ll need to remove infested buds and use an insecticide to control these pests.