Potassium is not part of the plant organic matter. The cytoplasm only contains this in the form of K+-ions. However, these are essential to the plant’s metabolism, especially respiration and evaporation. That is why potassium has a positive effect on the yield and the quality of crops. For example, it improves the production of carbohydrates. Ample supply of potassium is, therefore, required with crops that have a high potassium requirement. (potatoes and beets). There are two major salts containing potassium sold for fertilization. Sulfate of Potash (SOP) low in chlorine mainly used on vegetable crops and potatoes. Muriate of Potash (MOP) high in chlorine content mainly used for fertilizing crops like wheat, corn and grassland.