Susceptibility of the hot pepper (Capsicum annum L.) and the tomato (Lycopersicon esculentum Miller) to spent lubricating oil was investigated in soils supplemented with concentrations of oil ranging from 1-5% w/w. Treatment of soil with 4 and 5% spent oil consistently inhibited germination of both crops.Eighty-four days after sowing, the mean height and leaf area of C. annum in soil treated with 3% spent oil gave the lowest values. These were 3 14 ± 0 6 cm and 0 24 ± 0 01 cm 2 compared with respective values of 19 2 ± 0 2 cm and 2 9 ± 0 3 cm 2 for control plants. Premature death was observed in the case of L. esculentum plants treated with all tested strengths of spent lubricating oil.