Bioremediation of ex-situ crude oil contaminated soil to which Banana Stalk Ash (BSA) was added has been studied in this paper, based on Total Petroleum Hydrocarbon (TPH) content. Four samples each were contaminated with 20g, 40g and 60g respectively of crude oil and 0g, 20g, 40g and 60g of banana stalk ash was added respectively to the four samples to produce twelve samples. Analysis of samples for TPH at two weeks interval after pollution up to the eight week revealed that bioremediation occurs naturally and is more profound within the first two weeks and the percentage reduction in TPH increased with increase in BSA content and level of crude oil contamination, with a maximum of 90.1% TPH reduction obtained after eight weeks. Therefore, Banana stalk ash (BSA) is a good substitute to NPK fertilizer for bioremediation considering its ability to achieve a high percentage reduction in TPH and its low cost.
