Preventing Disease in Tomatoes 1. Rotate your crops: Since many Tomato pathogens live in the soil Plant tomatoes in a different spot in the garden each year. 2. Pinch off leaves with any signs of disease immediate and dispose of them in the trash to keep a possible infection from spreading. 3. Don’t work in the garden when tomato foliage is wet or you may inadvertently spread pathogens from plant to plant. Choose disease-resistant varieties when selecting which types of tomatoes to grow. 5. Remo