Potassium is necessary for plants to maintain their metabolic activities in a healthy way such as photosynthesis. The lack of potassium in potatoes is manifested by the appearance of bronze-colored spots on the leaves, and the appearance of black spots on potato tubers. Potassium deficiency causes a decrease in starch, which is high in potatoes, and premature darkening. In addition, potassium deficiency lowers the plant’s resistance to diseases, thus generating inefficient and poor quality crops.