What Kinds of Pesticides to Use for Roses

If you’ve discovered a pest infestation on your roses, don’t panic. Most gardeners will encounter these unwanted critters at one point or another. While we try to avoid spraying our roses with pesticides, it’s sometimes a necessary measure. This guide will help you understand the differences between different types of pesticides and determine which is best for your roses. 

Common Rose Pests to Watch out For

Every so often, we find unwelcome guests on the foliage and buds of our roses. The most common of these are:

• Aphids: Often clustering together on the buds of your roses, these light green, pear-shaped insects are easy to spot. 

• Spider mites: Difficult to see with the naked eye, these pests can be identified by browning of the foliage and the webbing they form on your roses. 

• Japanese beetles: Often found snacking on the foliage and blooms of your roses – these insects have metallic, shiny, green & copper-colored bodies about ½ inch long.

• Thrips: Measuring less than 1mm – these tiny dark-winged, pale-bodied insects thrive inside the buds of your roses. 

• Sawfly larvae (rose slugs): You might mistake these pesky critters for caterpillars with their ½-long green bodies and orange/brown-colored heads.
  

Regularly inspect your roses so you can catch these tiny invaders early and stop them in their tracks!

Understanding Pesticide Categories

Before choosing a pesticide, it’s important to understand 3 categories that will help you determine which ones you should use. 

Organic vs. Chemical Pesticides

Organic or natural pesticides should always be the first line of defense when eliminating pests on your roses, but there are times when chemical pesticides may be necessary. While chemical options produce quick and effective results, they can be harmful to beneficial insects (such as bees, butterflies, and ladybugs) and cause long-term damage if used regularly. 

Systemic vs. Contact Pesticides 

If you’re looking for a quick and easy solution to get rid of pests, you’ll want to use a contact pesticide. Contact pesticides allow you to target specific areas of the plant and come in direct contact with the insects – producing almost instant results. However, these results don’t last. Once dry, the efficacy wanes and new pests may move in.

Systemic pesticides are absorbed by the plant and circulate throughout its tissue. When pests feed on the foliage or buds, they ingest the pesticides. These offer long-lasting protection (around 3-6 months), but can harm both the environment and pollinators that naturally protect your roses.

Broad Spectrum vs. Selective Pesticides

Just as their names suggest, broad spectrum pesticides kill all types of pests (good and bad), while selective pesticides target specific ones.

Whenever possible, choose a pesticide that is natural and only goes after the bad pests.

Organic & Eco-Friendly Pesticides

There are a number of organic solutions that can help deter pests from feeding on your roses without harming the environment or beneficial insects. The most common are:

• Neem oil: Works by smothering the insect and interrupting their breeding cycle.
  Apply every 7 days until the pests are out of sight. 

• Insecticidal soap: Works by drying out the insect’s exoskeleton – resulting in dehydration and death. Apply every 3-6 days, depending on the severity of the infestation.

• Horticultural oil: Works by blocking the insect’s breathing pores – resulting in suffocation and death. Apply once a week as long as pests are present.

• Diatomaceous earth: A fine, powdery substance that penetrates the insect, damages its protective covering and dries it out – leading to dehydration and death. Reapply after heavy rainfall.

For any pesticide, early morning or evening application is best. This allows the solution to settle into the plant before the sun can dry it out. 

*Although these solutions are non-toxic, it’s still important to take safety measures. Always follow the instructions on the label and wear gloves and eye protection while spraying any kind of pesticide.

Best Pesticide Options by Pest

While we wish there were one blanket solution for all the pests we could encounter on our roses, each one may require a slightly different treatment. Here’s what we recommend for each of the common rose pests:

Aphids: Insecticidal soap or neem oil
Spider mites: Insecticidal soap, neem oil, or horticultural oil
Japanese beetles: More resilient against pesticides. Try neem oil, or easily pick them off the foliage by hand.
Rose slugs: Insecticidal soap, neem oil, Spinosad, or handpicking. 

When to Consider Chemical Pesticides

Use chemical or synthetic pesticides only as a last resort – when the infestation is so severe that natural options just won’t do the job. If you’ve come to the conclusion that chemicals are the only way to attack the problem, we recommend using the ones with the least environmental impact. Be careful not to overuse these products – as they can build up in the soil and cause resistance over time. 

Integrated Pest Management (IPM) Approach

Integrated pest management (IPM) uses a combination of control methods rather than relying on pesticides. The 4 controls in IPM are:

• Biological: Let beneficial insects (such as ladybugs & green lacewings) naturally repel pests and prevent them from feeding on your roses. 

• Cultural: Create an unappealing environment for pests by cleaning up the area surrounding your roses. Remove any weeds, dead leaves, or rotten fruit.

• Mechanical: Derail pests by hand-picking them off the foliage and buds, spraying them off with a hose, or creating barriers with netting. 

• Pesticides: When all else has failed, spray your roses with a pesticide that does as minimal environmental harm as possible. Always try organic pesticides before resorting to chemicals.

When the use of pesticides becomes absolutely necessary to control an infestation, there are plenty of options available. Try to choose one that’s eco-friendly and does no harm to beneficial insects, and always follow safety precautions during application. Visit April & Ashley to browse our collection of premium rose bushes and bouquets – delivered straight from our farm to your doorstep.

Happy gardening!

April & Ashley