Phosphorus (P) is a poorly soluble plant nutrient. Therefore, P uptake by the potato crop is primarily through root interception and short distance diffusion. This limits the percentage of soil supplying P to potato roots. Placement of P fertilizer is a management variable that can influence P uptake and P use efficiency, thereby improving tuber yield and quality. Recent studies conducted at Colorado State University’s San Luis Valley Research Center, USA, has shown that blending orthophosphate fertilizers with 10-34-0 reduces required P fertilizer cost and improves P use efficiency, as well as increase potato tuber yield and quality, compared to using 10-34-0 as sole source of P fertilizer. Information on placement method of blended P fertilizers for maximum use efficiency and tuber performance has not been documented. Studies were conducted at Colorado State University’s San Luis Valley Research Center, USA, with the objective of evaluating the effect of blended liquid P fertilizer placement method on Russet potato performance in the field. Three orthophosphate fertilizers each blended with 10-34-0 were evaluated under three placement methods (banding, in-furrow, and banding in-furrow application). Banding of blended liquid P fertilizers increased medium size (4-10 oz) tuber yield by 22%, compared to in-furrow application. In-furrow application of blended liquid P fertilizers increased production of premium size (> 6 oz and > 10 oz) tuber yield by 8 and 49%, respectively, compared to banding application. Results from this study suggest that appropriate liquid P fertilizer placement method can enhance sustainable potato production.
