Recent research in Arkansas has shown that foliar application of potassium to cotton can correct K deficiencies during the growing season. (3) This discovery has created considerable interest in the use of liquid potassium fertilizers. Potassium nitrate solutions have been most widely used for foliar application to cotton. While a very good source of plant food, potassium nitrate has limited solubility, a negative heat of solution and requires hot water for rapid solubilization. KTS^® (potassium thiosulfate) is suggested as an alternative to potassium nitrate as a foliar fertilizer. The advantages of KTS^® as a foliar K material are discussed.