One of the most critical components for healthy plants is potassium. Potassium leeches out of soils easily, causing frequent deficiency in plants. Curling leaves and brown or yellow spots often indicate a potassium insufficiency. Potassium-starved plants are far more likely to succumb to drought stress, fungal attach or frost damage, and produce much smaller fruit. Apply fast-acting Nutri-K directly to leaves as needed. Nutri-K uses the same patented technology as Nutri-Cal for quick delivery directly to the plant. The two products can be used in combination. For use on fruits, vegetables, and ornamentals. Mix 1 to 3 oz. per gallon depending on crop.