Rose: Root weevils

• Categories: Flowers Ornamentals Rose Rose Insects
• Last review date: 2025-07-28 11:22

Biology

Several species of weevils feed on roses.

Adult weevils feed on the leaves, leaving small, ragged notches along the edges. They may also feed on the flowers.

They are wingless gray, brownish, or black beetles that feed at night.

The larvae live in the soil and feed on the roots.

Management Options

See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.

Non-chemical Management

Select non-chemical management options as your first choice!

• Hand-pick night-feeding adults to reduce numbers.
• Application of beneficial nematodes which kill the larvae may be useful for controlling severe infestations. The nematodes are used as a soil drench in moist soils over 55 degrees F (mid-fall in western Washington).

Chemical Management

• Adult control should begin when adults emerge late May-June or when notching begins to occur on new leaves.

Approved Pesticides

If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.

• Garden Safe Fungicide 3 Concentrate - OMRI - [Organic]
  Active ingredient: clarified hydrophobic extract of neem oil
  EPA registration number: 70051-2-39609
• Safer Brand BioNEEM Multi-Purpose Insecticide and Repellent Concentrate [Organic]
  Active ingredient: azadirachtin
  EPA registration number: 70051-6-42697
• Safer Brand Garden Defense Multi-Purpose Spray Concentrate [Organic]
  Active ingredient: clarified hydrophobic extract of neem oil
  EPA registration number: 70051-2-42697
• This list may not include all products registered for this use.