Irrigated vegetable production is an important agricultural activity and a significant source of income for millions of smallholder farmers in the Sahel. There is little information on the potential effects of intensive vegetable production using African Market Garden (AMG) technology on vegetable yields and soil chemical properties. Three contiguous 500-m 2 plots were established to evaluate three vegetable management practices: (1) AMG, (2) Improved Management (IM), and (3) Farmer Practice (FP). These management practices were arranged in a randomized block design. AMG and IM management practices produced higher yields as compared to farmer practices. Tomato and onion yield for IM were 50 and 300% higher than for AMG, respectively; while yields for FP were consistently lower. The soil chemical properties at the end of the experiment displayed marked changes in all treatments compared to the initial soil status. Except for pH, which decreased by 0.2, 0.4, and 1.1 pH units, respectively, for FP, IM, and AMG, soil chemical properties increased as a direct response to management practices. These findings indicate that regular and high rates of manure application combined with mineral fertilizer enhance sandy soil fertility in the Sahel. These findings are important for developing sustainable vegetable production in the Sahel.