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

Non-Chemical Management

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).

Select non-chemical management options as your first choice!

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides

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

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.

ferti-lome Broad Spectrum Insecticide
Active ingredient: bifenthrin | EPA reg no: 53883-228-7401
Garden Safe Fungicide 3 Conc - OMRI - [Organic]
Active ingredient: clarified hydrophobic extract of neem oil | EPA reg no: 70051-2-39609
Safer Brand BioNEEM Multi-Purpose Insecticide & Repellent Conc [Organic]
Active ingredient: azadirachtin | EPA reg no: 70051-6-42697
Safer Brand Garden Defense Multi-Purpose Spray Conc [Organic]
Active ingredient: clarified hydrophobic extract of neem oil | EPA reg no: 70051-2-42697
This list may not include all products registered for this use.

Images

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Caption: Adult root weevil damage Photo by: E.P. Breakey
Caption: Root weevil larval damage Photo by: A.L. Antonelli
Caption: Root weevil larvae Photo by: A.L. Antonelli
Caption: Black vine weevil adult and leaf damage Photo by: A.L. Antonelli

WSU Extension

Hortsense