Since most Southeastern U. S. soils ate acid, crop yields can generally be improved by liming surface soil. However, it is not known if plants will respond to deep incorporation of lime. Field experiments were conducted on two soils (Rhodic Paleudult and Typic Paleudult) at three locations in central and south Alabama to evaluate the effect of depth of Incorporation of surface‐applied lime on root system development, plant growth, and yield on acid soils. Soil pH ranged from 4.1 to 4.8 before liming. Sufficient lime was surface‐applied and incorporated to the 15, 30, and 45‐cm soil depths to increase pH in the treated zone to at least 6.0. All plots were initially chiseled to the 45‐cm depth to reduce physical differences resulting from subsequent lime incorporation. Depth of rooting, soil water extraction, plant height, and cotton (Gossypium hirsutum L.) and corn (Zea mays L.) yields were increased by lime. Based on the results from these two soils, incorporating lime to the 30‐cm depth is sufficient to obtain a satisfactory root system for high crop yields of cotton and corn.