Instant soil pH and lime-requirement determination methods will result in continuous and variable application of liming materials that will be invaluable for precision farming. The kinetic reaction of the modified Adams-Evans soil buffer solution and soil was determined by a batch technique. The buffer pH of twelve representative Alabama soils was determined at 15, 30, 60, 90, 120, 150, 180, 210, 240 and 900 seconds in four replications according to the modified Adams-Evans method using a magnetic stirrer. The buffer pH solution and soil kinetic data were characterized using first-order kinetic equations with highly significant correlations. The predicted buffer pH values were also significantly correlated to values determined by standard laboratory method. A simple linear algorithm kinetic relationship can be used to predict buffer pH values at any suitable time for on-the-go field buffer pH measurement and lime application.