Potato (Solanum tuberosum L.) production requires high P availability with potential negative environmental and nutrient uptake effects. Impacts of high available P on species in potato cropping rotations are not adequate understood, nor have the causes of reduced yield and quality from excess P been fully explored. Antagonistic interactions with cationic micronutrients such as Zn and Mn are plausible explanations. Two hydroponic experiments were conducted with Russet Burbank potato to elucidate P and Mn relationships and associated interactions with other nutrients. In the first experiment, P solution concentration was constant at 128 μM while Mn concentration varied: 0.05, 3.2, 9.5, 28.5, 85.5, 256.5, and 769.5 μM Mn. In the second, plants were grown at each of three levels of P and Mn with Mn at 0.05, 9.5 and 769.5 μM and with P at 32, 128 and 1024 μM. Potato yield maximized between 9.5 to 85.5 μM Mn and declined at deficient (0.05 and 3.2 μM) or toxic (256.5 and 769.5 μM) solution Mn levels. As solution Mn concentration increased, concomitant increases in top, middle and root Mn followed, P concentration initially declined followed by consistent increases in all plant tissues, but Zn concentrations varied depending on plant part. High solution P resulted in accumulation of Mn in potato roots but without impacting Mn in top or middle portions of the plant. This observation further supports the findings of the variable P/Zn experiments where high P resulted in increased root Mn which may indirectly impact Zn nutrition in potato. Thus, high Mn levels in potato did not directly reduce Zn or P content or promote Zn deficiency, but high P levels did increase Mn in roots and this could reduce the activity of Zn in potato (see companion poster “Phosphorus and zinc interactions in hydroponically grown Russet Burbank potato”).