(> 4 oz) tuber yield by 28% and 32%, respectively, when compared to pre-plant application of SOP with no KNO3 fertilizer (Table 2, left). SUMMARY Results obtained from this study clearly indicate that side dressing russet potato cultivar 'Canela Russet' with KNO3 fertilizer, up to row closure helps increase K uptake throughout the growing season, enhance early tuber bulking, and increases tuber yield. Frequent side dressing with liquid KNO3 fertilizer throughout the growing season is not recommended. Samuel YC Essah, Ph.D., is Associate Professor and State Potato Extension Specialist in Colorado State University's Department of Horticulture and Landscape Architecture. He is based in CSU's San Luis Valley Research Center. side Figure 2. Tuber Bulking dressing 1406 1356 1306 1256 1206 1156 1106 1056 1006 108 Days After Planting Blend + QROP side dress SOP + Spoon feed K SOP Pre-plant SOP + Liquid K side dress SOP + Dry + Liquid side dress 116 40 Spudman.com Tuber Bulking (g/plant)http://www.Spudman.com