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Common buckthorn · Rhamnus cathartica

What is eating my common buckthorn?

It is less common for pests to cause major damage to this shrub, but aphids or scale insects can occasionally appear. Check the stems and leaf undersides for sticky residue or small bumps first.

Not sure it's this? Check a photo of your plant for free

pests on a plant
Photo: Jules Verne Times Two, CC BY-SA 4.0

Check these first

  1. Look for sticky honeydew on the leaves or stems.
  2. Inspect the undersides of leaves for clusters of small insects.
  3. Check the stems for unusual bumps or crusty patches.

Likely causes

  1. Aphids

    Most likely

    How to tell: You will see clusters of tiny green or black insects on new growth. They leave behind a sticky substance called honeydew that can attract ants.

    What to do: Blast the insects off with a strong stream of water from your garden hose. If they persist, use a mild insecticidal soap spray once a week.

  2. Scale insects

    Possible

    How to tell: Look for small, hard, brown bumps on the stems that look like tiny shells. These insects suck sap and can cause the plant to lose vigor.

    What to do: Scrape the scales off by hand if the infestation is small. For larger issues, apply horticultural oil during the dormant season to smother the pests.

Pests on other plants

Find out what's wrong with your common buckthorn

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

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When to worry

Worry if you see significant yellowing or stunted growth alongside the pests. It is normal to see a few stray insects on a healthy outdoor shrub.

Stopping it coming back

Encourage beneficial insects like ladybugs to visit your garden. Keep the plant healthy with proper water and light to help it resist infestations.

Common buckthorn: pests? Check yours with a photo

Every plant is a little different. Take a photo of your common buckthorn and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

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Questions people ask

Will these pests kill my buckthorn?
Usually not, as the plant is quite resilient. Most infestations are minor and can be managed with simple physical removal.
Do I need to use harsh chemicals?
Avoid harsh chemicals as they can harm the beneficial insects that help control pests. Water sprays and insecticidal soaps are much safer options.

Guides to these causes

More problems with Common buckthorn

Back to the Common buckthorn guide

This article was generated with AI on from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.