Tillage and crop rotation can be very beneficial in controlling frogeye leaf spot. In tillage, it's important that residue is completely buried. If infection does occur, it is best to rotate out of soybeans for at least one year, and then follow the nonhost crop with a resistant variety of soybeans.
Foliar fungicides are most effective in controlling frogeye leaf spot outbreaks. Applications are most effective when applied from R1 to R3. Fungicide application becomes very economical if applied before spots number greater than 2 every 25 feet. Please contact your local plant pathologist to learn what is most effective in your area and how to use it best. Always read and follow all label instructions.
Soybean varieties have been developed that are somewhat resistant to frogeye leaf spot. However, it is important to select varieties that are more resistant to diseases with greater impact than frogeye leaf spot.