The measure of acidity or basicity of a solution. Acidic solutions have a pH level ranging from 0 to 7.0. Neutral pH level is considered 7.0, and basic solutions have a pH range from 7.0 and 14. Soil pH directly influences the vitality and quality of a lawn. Most lawn grasses grow best in a pH range of 6.0 to 7.0. In some cases during lawn care, lime is added to lawns to raise the pH level of acidic soil to the ideal range.