The mulch reduces the splashing of fungal spores onto plant foliage. Placing the mulch around plants in early June allows the soil to warm up in the spring. Avoid wetting tomato foliage when watering. Apply water directly to the ground around plants with a soaker hose or slow running hose. While cultural practices may help control tomato blights, fungicides are often needed.
Thorough coverage is essential.
Be sure to spray both the upper and lower leaf surfaces as well as the centers of the plants. Spray to the point of runoff. If blight occurs, remove and destroy infected leaves as they appear. Prompt removal of infected leaves may slow the progress of the, blights. At the end of the gardening season, remove and destroy all infected tomato plants.