The field experiment was carried out during the 2018 growing season at the Federal College of Forestry, demonstration farm to determine the efficacy of potassium fertilizer levels on the growth and yield of the sweet potato (Ipomoea batatas L). The treatments comprises of five levels of potassium fertilizer (0, 50, 100, 150 and 180 kg/ha) that were laid in a Randomized Complete Block Design (RCBD) replicated four times. The application of 200 kg /ha of potassium fertilizer produced the longest vines (70.60cm), the highest number of leaves (284.60), branches (16.40), number of flowers (12.20), number of tubers (13.20), and larger diameter tubers (6.42cm), while the application of 150Kg/ha produce the highest yield (23.47tons/ha). To achieve high yield of sweet potato, higher doses of potassium fertilizer should be applied by the farmers in the study area.

Keywords : Sweet potato, Potassium fertilizer, Growth, Yield components.