This may serve as a weed control mechanism. Summer annuals may heavily invade turfs under only moderate maintenance, however, dormant turfs will not support crabgrass germination and development. These grasses generally recover and return to normal levels of quality in cooler weather. The decision as to when to irrigate will depend on the quality of the turf desired, the availability of water, the probable duration and severity of the drought conditions, and probably most important, the budget. Duration of Irrigation To maintain a high-quality appearance throughout the growing season, an area should be irrigated as soon as the turf shows symptoms of wilting.
Visual symptoms can be a rapid darkening in color or grayish appearance.
Ideally, all turfs should be irrigated to saturate the root-zone area thoroughly. Following irrigation, the turf should not receive water until further signs of wilting appear. Apply enough water to moisten the soil to a depth of at least 6 in. For a medium-textured soil, this might be equivalent to 1 in. The amount of water received by the soil surface can be measured simply by placing several coffee cans or other receptacles within the irrigation zone.