Question:
If I decide to water my lawn during prolonged dry conditions, how and when should it be watered?Answer:
The appearance of the turfgrass is the best way to determine when to water the lawn. The ideal time to water a lawn is at the first signs of water stress. Turfgrasses that have adequate supplies of water are normally dark green in color. For cool-season grasses, such as bluegrass, the first signs of stress are a bluish green color and footprints that remain in the turf after walking across an area.
Most lawns in Iowa need 1 to 1 1/2 inches of water per week. When watering the lawn, apply this amount in a single application or possibly 2 applications 3 or 4 days apart. Avoid frequent, light applications of water which promote shallow rooting and lush growth. Lush, shallow-rooted turfgrass is less drought tolerant. To determine the amount of water applied by the sprinkler, place several straight-sided cans within the spray pattern. Then measure the amount of water collected in the cans with a ruler.
Early morning (5 to 9 am) is the best time to water the lawn. A morning application allows the water to soak deeply into the soil with little water lost to evaporation. When watering is completed, the turfgrass foliage dries quickly. Watering at midday is less efficient because evaporation is rapid and strong winds may cause uneven water distribution. Strong midday winds may also carry water onto driveways, patios, or streets, wasting considerable amounts of water. Watering lawns in the evening or at night may increase disease problems.