The Best Time to Water Lawns With a Sprinkler System

Dangers of Too Much or Too Little

• Daily, light watering that dampens the soil less than an inch will not help in droughts. Lawns will dry out in a day and can become weak with shallow-rooted grass. On the other hand, drowning the lawn creates another set of problems. Overwatering the lawn damages the root system because of lack of oxygen. Soggy soil does not retain oxygen; plant roots that need oxygen die. Sometimes gardeners think dying grass means a lack of water and the cycle is aggravated.

Sprinkler Timing and Water Depth

• Weekly soaking the soil 4 to 6 inches is preferable for healthy lawns. According to the Colorado State Extension, shallow containers placed around the lawn while sprinkling help to decipher sprinkler timing. The container's average water depth multiplied by two equals the inches of water per hour coming from the sprinkler system. How long it takes to achieve the ideal moisture depth is also dependent on soil condition. Heavy clay lawns may require irrigation clocks set at five-minute intervals to avoid runoff.

The Best Time of Day

• Sprinkler systems are best set when there is a low chance of water evaporation. In general, the weather is cooler with higher humidity and less wind between the hours of 10 p.m. and 6 a.m. During this period of low water use, the spray can be more evenly distributed because of higher water pressure. Grass blades are susceptible to turf diseases when wet for longer than 14 hours. This period gives the lawn a good soaking to last through the day and time to dry.

Exceptions to Watering Rules

• Freshly seeded grass and lawn pallets need initial, frequent watering to become established. The first two weeks are crucial to keep a new lawn from drying out. Keeping a young lawn moist on hot, windy days could require four or five watering sessions. After a month, the lawn may be considered established. Most lawns do not require winter watering. Areas that experience dry, airy winters are vulnerable to winter grass mites without occasional irrigation.