The survival and growth of planted woody seedlings in drylands are constrained by severe water stress, yet silvicultural measures that enhance soil water availability may substantially improve establishment success. This study evaluated the effects of biochar and deficit irrigation on the survival, growth, and ecophysiology of Faidherbia albida seedlings over two years. Biochar was applied at 38 g kg(-)(1) soil pit(-)(1), and deficit irrigation supplied 353 mm of water, corresponding to 44.5% of the dry season crop evapotranspiration. The seedlings treated with deficit irrigation and with combined biochar and deficit irrigation exhibited the highest survival rates (76.7% and 73.3%, respectively) compared with the control. Growth performance was significantly enhanced under combined biochar and deficit irrigation, which increased the seedlings height and diameter by 104.5% and 62.5%, respectively, and resulted in significantly greater (P < 0.01) branch number than the control. Relative growth rate (RGR) in height was elevated by 33.3% in the final dry season, and total biomass increased by 221% under biochar and deficit irrigation. Physiological measures indicated that these effects were mediated through enhanced gas exchange and water use efficiency (WUE). Height RGR was positively correlated with photosynthetic rate (P < 0.05), indicating a strong physiological basis for growth enhancement. These findings demonstrate that the combined application of biochar and deficit irrigation significantly improves the establishment and growth of F. albida seedlings under dryland conditions, supporting its wider promotion as a key agroforestry species.