These both attack the vascular system of the plant and interfere with the movement of water into the foliage. If plants die from Verticillium or Fusarium, do not replant mums into the same area. Rhizoctonia and Pythium are two other fungi that cause similar symptoms. These cause lesions on the stems and roots resulting in wilting of the foliage above the affected stem or root. Most leaf spots are caused by one of many fungi.
Infected leaves produce defined, small, brownish spots.
Often spots will increase in size and form a large brown area. Do not irrigate late in the evening and try to avoid splashing soil on foliage. This fungal disease creates a white powdery mold on the upper leaf surface. In severe cases the new growth may be distorted. Early detection of this disease is very important.