The present disclosure provides methods and compositions for treating fungal diseases of plants. In one embodiment, an anti-fungal aqueous composition can comprise: a nitrogen source material having a total nitrogen content in an amount of about 0.1 wt % to about 0.5 wt % of the total weight of the composition, a phosphate source material having total phosphate content in an amount of about 0.05 wt % to about 0.15 wt % of the total weight of the composition, a potassium source material with a soluble potash content in an amount of about 0.05 wt % to about 0.15 wt % of the total weight of the composition, and a sulfur source material in an amount of about 0.005 wt % to about 0.02 wt % of the total weight of the composition.
