Lime is most effective when it is applied to a lawn being prepared for planting in the fall, winter or early spring, states West Virginia University. Lime may be applied at any time of the year on lawns that are already established.
Lime does not move horizontally when applied to the lawn, so it must be spread evenly across the entire area. Using a spreader typically makes even distribution of the lime over the lawn easier, though if the ground is too wet, it may not distribute across the lawn evenly. Lime also moves through soil very slowly, at an average of 2 inches every two years. The alternate freezing and thawing that occurs in early spring, as well as early spring showers, allow the lime to better penetrate into the soil.
Typically, lime should be applied to the lawn every three to five years. Lime is used to correct the soil acidity of the lawn in order to create favorable conditions for grass growth. The optimum amount to use is determined by the type of soil, the soil's acidity level and the type of lime being used. Soil that is light and sandy requires less lime than soil that has high levels of silt and clay. The best way to determine how much lime is necessary is to test the soil before application.