Lime is often the best place to start when trying to sweeten the soil. Typically 2 tons of raw ag lime will increase the pH 1 full point, taking a pH of 5.5 to a pH of 6.5. Raw lime takes 3 months to start changing the pH and normally takes about 9 months for the full effect. Lime makes fertilizers more efficient and available to plants. Most grasses like the pH around 6.1, while most broadleaf plants like soy beans, alfalfa, and clover prefer a pH of 6.5.
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