The spots are covered by white or grayish mold. The stems are distorted and the blossoms fail to develop. As the stem bases are infected the plant collapses. Pick off infected leaves. No chemical control is listed.
Powdery mildew causes a white powdery growth on the leaves.
Spray with benomyl or sulfur. Verticillium wilt decline and death of the plants. No chemical control is available for this disease. This information is for educational purposes only. References to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned.