The March issue of Kentucky Living talked about David Bunch, who treats his soil with a fungicide before planting tomatoes. What fungicide would one use for this purpose?
The Gardener’s Answer
Hi, Sharon: Tomatoes are susceptible to several fungal problems, the most common being early and late-season blight. These soil-borne pathogens over-winter in the soil or on plant debris, so if your tomatoes have been infected by any fungal problems in the past it is important to take preventive measures. Good cultural practice is the most effective means of avoiding future problems. Crop rotation is especially important when it comes to soil-borne pathogens. It is best to move your tomatoes (and any other plant in this family) to a different space in the garden every two to three years. If there are pathogens in the soil, not planting host crops in that space will essentially starve the pathogen and allow you to plant tomatoes there in the future. Mulching is another way to protect fruit from these pathogens and will help stop spore dispersal. Spraying a fungicide or using a soil drench before planting would be a preventive measure, but there are many harmful fungicides out there that are not recommended for use on any edibles. If you do use a fungicide on your tomatoes, make sure you use a product that is organic and labeled for use on vegetables. If there is an established population of pathogens, cultural practices will be safer and more effective than any fungicide.