Common hosts include cabbage and related cole crops, dandelion, endive, mustard greens, parsley, turnip, tomato, potato, spinach, pepper, beet, celery, lettuce, and chard. Greenhouse plantings are very susceptible. Infestations typically begin on the lowest leaves of the plant and damage is caused by direct feeding and transmission of disease. Honeydew secreted by the aphids may support black sooty mold growth.
Winged forms migrate to other host plants in the spring.
During these flights, aphids may spread viral diseases from infected volunteer plants and weeds to healthy crop plants. Movement between host plants continues through summer and fall. Successive generations of females, usually wingless, are produced throughout the year. Winged migrants develop whenever overcrowding occurs or food becomes scarce. Outdoor infestations are most common during the spring and fall and decline during the hottest months of the summer.