How to Manage Pests

Pests in Gardens and Landscapes

Cavity spot—Pythium violae

Cavity spot is characterized by elliptical to irregularly shaped depressed lesions oriented across the mature carrot tap roots. Individual lesions are usually less than 0.5 inch in diameter, but can be much larger, especially on processing varieties. Infections can occur anywhere along the tap root, but lesions tend to be more abundant on the upper third of the root. Lesions begin as pinpoint, sunken spots and generally enlarge as roots mature.



The fungus that causes cavity spot is favored by low soil temperatures. Practice 3-year crop rotations with nonhosts of the disease such as tomato, watermelon, corn, and potato. Do not overirrigate. Harvest carrots soon after they mature because older carrots are more susceptible to infection. All carrot varieties are susceptible.

Cavity spot on carrots
Cavity spot on carrots

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/GARDEN/VEGES/DISEASES/cavityspot.html revised: April 25, 2014. Contact webmaster.