Gray Mold (Beans) Description: Gray mold is most common when flowering occurs during a cool period of high humidity. Crowded plants with a dense canopy of leaves also encourage gray mold. Infection begins in the flower and spreads to the pod. . Solution: Rows should be thinned to allow breezes to dry leaves. Avoid overwatering and overfertilizing with nitrogen. Apply Soap-Shield® Fungicidal Soap as soon as flower buds can be seen, and continue applications as long as plants are flowering