AbstractIntegrating a perennial forage grass like bahiagrass (Paspalum notatum Flugge) into the traditional rotation of cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) increases yields and reduces irrigation needs in the Southeast United States. However, the long‐term effects of this sod‐based rotation (SBR) on soil properties remain unclear. Eighteen years after establishing SBR and the traditional rotation, we collected samples to a depth of 120 cm in 30‐cm increments and measured soil carbon and other soil properties (e.g., Mehlich‐extractable nutrients). Soil C was 6% higher with SBR in the top 30 cm of soil after 18 years, with no impact on soil C in deeper soil layers. Similarly, there was no effect of SBR on other soil properties (soil texture, pH, and Mehlich‐extractable P and Mg), except for lower soil K in SBR. Our results indicate a limited effect of SBR on soil C and other properties in this system where SBR is not grazed and where strip tillage and cover cropping were implemented in both rotations.