Potassium is frequently applied to irrigated potato in Manitoba. Field experiments were conducted at two sites in each of 2006, 2007 and 2008 to assess effects of rate and timing of potassium chloride (KCl) application on the yield, quality, and nutrient status of irrigated potato ( Solanum tuberosum 'Russet Burbank') in southern Manitoba. Preplant application of KCl increased total and marketable yield at one site, and tended (0.05