By Md Rasel Parvej
LSU AgCenter
Soil pH indicates whether lime is required but not how much. Lime is needed if the target soil pH, which varies by crop, is 0.2 units higher than the actual soil pH.
Buffer pH indicates how much lime is required. Soils with low buffering capacity (high buffer pH) and a small difference between initial and target pH values require less lime. Conversely, soils with high buffering capacity (low buffer pH) need more lime, even for small pH adjustments.