An on-station study at Fumesua and Ejura in Ghana with two yam varieties (Pona and Dente), seedbed option (ridge and mound) and NPK fertilizer rates (0, 45-45-60, 60-60-60 and 60-60-80 kg ha-1 N-P205-K20) revealed significant (p < 0.05) increases in soil carbon and phosphorus with fertilizer application to yam.