Anthony Reed 1000 ASU Dr.# 479 Alcorn State, Ms 39096-7500  areed@lorman.alcorn.edu

Soil types, grass species, turf management and water quality influences the amount of supplemental water and the watering frequency required for lawn. Sandy, coarse-texture soils absorb water at a much faster rate than finer textured soils, but retain less moisture. Because of this, sand soils require frequent applications of water at lighter rates. Clay soils, however, retain more moisture and require less frequent watering. Clay soils absorb water very slowly so application rates should be slower and extended over a longer period. The infiltration rate and water retention of the loam soil is between that of sandy soil and clay soil.

Grass species and management practices largely determine the amount of supplemental water required for lawns. Grasses with good drought tolerance should survive without watering. They will become straw-colored and dormant during extended dry periods. But with the first significant rainfall, or with watering, these grasses recover. Grasses with only fair or poor drought tolerance may not survive extended droughts without watering.

Management also influences the amount of water needed to maintain a healthy, great lawn. Frequent fertilization and close mowing tend to increase the amount of watering required. Application of soluble nitrogen fertilizers during last Spring and Summer months significantly increase water use. Spring and Fall fertilizers applications meet most grass requirements for nutrients without significantly increasing water needs.

During hot, dry conditions raise mowing heights to reduce water needs. Grass mowed at 2 to 3 inches maintains a deeper root system than grass mowed at 1 inch. Deeper roots need less supplemental water. Mow St. Augustine, Bluegrass, and tall Fescue lawns at 3 inches during dry weather. Do not mow Bermudagrass and Zoysia higher tan 2 inches.

The quality of the water used can influence the amount needed to keep a lawn health. In some areas of the state water has a high salt content. If this is a problem, select a turf grass with good salt tolerance and thoroughly wet the soil during each application. Light, frequent applications of water high in salt cause an accumulation of salt near the surface.