Forage crops such as alfalfa remove large quantities of potassium (K) on an annual basis. When manure application is not an option, fertilizer must be purchased to supply K to alfalfa. Potassium can impact plant health, potentially affecting the ability of alfalfa to overwinter. Under-application of K can result in less tons produced per acre. While K fertilizer has historically been cheap compared to the other major macronutrients, supplying removal rates of K to alfalfa annually can result in a significant expense to alfalfa producers.