The Best Time for Lawn Irrigation

Grass Type

• Lawns need to be irrigated based on their drought tolerance. For example, cool-season grass types such as bentgrass, fescue, ryegrass and bluegrass need regular irrigation, according to Colorado State University. These grass types typically need regular irrigation to stay alive during the heat of the summer. Warm-season grass varieties such as zoysia, Bermuda and St. Augustine are more drought-tolerant during the summer months. Also, these grass types go dormant in the winter and do not need irrigation.

Local Restrictions

• Local city and county municipalities place water restrictions on locals. In fact, it is important to find out what day and at what time it is legal to water your lawn. For example, the Southwest Florida Water Management District requires those with even addresses to water their lawns on either Thursday or Sunday before 10 a.m. and after 4 p.m. If you've recently seeded your lawn, there are special provisions that allow you to keep the soil moist for seed germination.

Best Time of Day

• The best time of day irrigate your lawn is between 10 p.m. and 6 a.m., according to Colorado State University. Between these hours, the weather is cool, and there is less risk of soil evaporation. In addition, the grass is generally moist with dew during these hours, which reduces the risk of fungal diseases. Fungal diseases are more likely to infect your lawn when grass blades have been kept wet for longer than 14 hours.

Other Factors

• Avoid watering lawns when they do not need water. The best time to irrigate is when your lawn actually needs water. In fact, irrigating just to irrigate can lead to fungal diseases. To know when your lawn needs water, examine the grass blades for signs of wilting. Generally, lawns need 1 to 1-1/2 inches of water per week. If your lawn receives less than 1 inch of water from rainfall, irrigate the lawn. An easy way to tell how much water your lawn has received in a week is by placing tuna cans in the yard. When the cans are filled halfway with water, the lawn has received 1 inch of water.