Rainfall alone usually sustains a healthy lawn. If, however, irrigation is needed, try to do the following:
Water during the early morning.
This minimizes water loss from evaporation and allows the sun to dry the leaf blade before disease sets in.
Water deeply and infrequently.
Soak the lawn deeply instead of giving it a quick mist. Frequent lawn watering often encourages shallow rooting and may predispose the lawn to increased disease and greater susceptibility to stress injury. Watering deeply and less frequently provides for improved turf growth and increased water conservation compared to light, frequent watering.
Wet the soil to a minimum depth of 4 to 6 inches or about 1 inch of water per week. Placing several empty cans (tuna or cat food cans work well) under the sprinkler allows you to determine when an appropriate amount of water has been applied.
Successful germination depends on ample moisture at the soil surface. Keep the seeded area moist until the seed emerges. The seedlings need frequent, gentle watering until they are ½ to 1 inch tall. When climatic conditions allow, reduce watering to several times a week at a depth of 1 to 2 inches. Decrease frequency and increase depth of watering as seedlings mature.
Summer brings the heat. It can also bring drought conditions when you least expect it. When a swelter begins to take a toll on your lawn, many grasses will try to survive by entering a dormant stage where they drink less water and stop growing. Daytime temperatures in the 80’s (F), lawns can survive for 3-4 weeks, whereas climates in the 90’s reduce that survival timeframe to 2-3 weeks. Irrigate lightly, about ½ inch, every 3 weeks to help your lawn get through the hot and dry summer months. This irrigation will not make a dormant lawn green again. Greening will start when conditions get cooler and wetter.
Installing a rain barrel helps preserve water, reduce water pollution, and lower your water costs all by capturing water from your roof's downspout into a rain barrel.