Few individuals, however, have a complete understanding of why lime is applied, how to determine if liming is needed, and how one should go about applying lime to the lawn. Also, most homeowners are not aware of the potential negatives of creating a pH too high by excessive application of lime. This fact sheet will briefly discuss the important role that liming can play in the production of a healthy home lawn and then will address the above questions. Lime is applied to soil, including that of home lawns, for the purpose of increasing the pH of the soil. Soil pH, a measure of the soil's acidity or alkalinity, governs the availability of many soil nutrients and can directly influence the vigor and quality of the home lawn.
Several factors are responsible for the formation of acidic soil conditions.
One primary cause is the leaching of base nutrients such as calcium, magnesium, and potassium from the soil. This occurs more frequently in areas of heavy rainfall or on heavily-irrigated turfs. A second cause is the use of acidifying nitrogen fertilizers. When the soil pH drops below 6.0, a number of nutrients necessary for proper growth become less available for use by the turfgrass plant. The result may be a less vigorous, unhealthy lawn.