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.
Learn more about Nutrical here