Cabbage Maggot—Delia radicum
The cabbage maggot is an exotic pest from Europe that has been in the United States since the early 1800's. It is a sporadic pest of many cole crops including cabbage, broccoli, cauliflower, Brussels sprouts, turnips, radishes, kale, and other crops of the mustard family. Occasionally, they will attack other vegetables such as beets and celery. It prefers wet, cool conditions.
Cabbage maggots damage and destroy root systems of all cole crops, riddling roots with tunnels when infestations are heavy. Tunnels provide entryways for pathogens. Young plants between seedling emergence until about a month after thinning or transplanting are most vulnerable.
The legless maggots are tapered and white in color, and are usually less than 1/3 inch in length. Newly hatched larvae feed and burrow into the roots.
Cabbage maggot flies resemble houseflies but are only about half as long, 1/4 inch. They are dark gray with black stripes along the body. Adults emerge between late March and early May. There are 3 to 4 generations per year.
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Identification and Control Information
- Pest Management Fact Sheet: Cabbage Maggots—University of Maine Cooperative Extension
- Fact Sheet: Cabbage Maggot (PDF)—Cornell University Insect Diagnostic Laboratory
- Fact Sheet: Cabbage Maggot (PDF)—University of New Hampshire Cooperative Extension
- Insect Pests of the Home Garden Fact Sheet: Cabbage Maggot (PDF)— Rutgers Cooperative Research & Extension
[Photos, left to right: Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org; © Queen's Printer for Ontario, 2009; Department of Entomology NC State University]