Cause Verticillium dahliae, a fungus widespread in soil and that affects a wide range of herbaceous and woody plants. The fungus gains entry through the root system; progress in the plant is primarily through the vascular system. Cool, moist soil favors the disease.
Symptoms Leaves turn yellow and dry up. Wilting progresses up the plant until the plant dies. A cross-section of a node near the plant base may reveal discolored vascular tissue.