How do I prevent fungal diseases in my garden?
Fungal diseases, such as powdery mildew, are a common problem in wet and humid environments. Raised beds reduce the risk of fungal infection by elevating plants above the ground to increase airflow and lower humidity. Avoid over-watering and watering at night, particularly in cooler weather. Be careful to water at the ground level so infected foliage doesn’t get wet.
Trellis plants and prune signs of infection to further improve airflow and reduce the spread of disease. Rotate crops and change mulches every year. Never grow tomatoes or potatoes, for example, in the same bed two years in a row where disease has occurred. Instead, follow with a crop from a different plant family or one that does not share the same diseases.
Compost tea applied regularly as a soil drench or foliar spray greatly improves natural disease resistance in plants and helps arm your garden with beneficial microorganisms that defend against fungal diseases.