To determine how long you need to water to get one inch, place a plastic container in your yard and set a timer. On average, it will take 30 minutes to get a half inch of water. So, 20 minutes, three times per week will give a lawn about an inch of water. This formula works best with healthy, well-cultivated soil.
If you're not sure how much time it takes for your sprinklers to spray an inch of water, you're not alone. A fixed spray head nozzle might take ~30 minutes to apply 1 inch of water, whereas a rotary nozzle could take 3x as long to apply the same amount.
2. Spray sprinkler heads can apply 1 to 2 inches of water per hour and can usually run 6 to 8 minutes before runoff occurs. If your system applies 2 inches per hour, set your timer one day a week for five 6-minute cycles with an hour in between for absorption.
For example, rotor sprinkler heads might require 20 to 30 minutes of straight watering time, while a traditional spray head zone will only need 5 to 10 minutes.
The ideal watering schedule is once or twice per week, for about 25 to 30 minutes each time. Taking care of a lawn doesn't have to be an overwhelming, all-consuming task.
In the late spring, rotor irrigation zones typically need to run 30-45 minutes per zone, and spray irrigation zones typically need to run 8-12 minutes. We recommend watering 2-3 days a week during late spring. In mid to late summer with extreme heat, your lawn will need more water.
The average system uses approximately 15-16 gallons per minute, per station. Here is an easy formula to help you calculate the approximate amount of water you are using each month.
To keep your lawn green and growing, it needs about 1 inch of water per week from you, rainfall or a combination of both. To measure how much is 1 inch of water, set a group of flat-bottomed cups at 5- to 10-foot intervals from the base of your sprinkler to the edge of its reach.
Therefore, an “inch of water” is 0.62 gallons per square foot of garden area. Unless you use a gallon jug to water a square foot garden, this number may still leave you wondering how to obtain that inch of water or 0.62 gallons per square foot.
Nothing should be in that area between the bottom of the sprinkler heads and the imaginary horizontal plane parallel to the ceiling that is 18 inches below. This is done to allow an even and unobstructed spray pattern from the sprinklers when triggered to extinguish the fire.
A typical sprinkler system with pop-up rotary heads uses approximately 15 to 16 gallons of water per minute per station. An Irrigreen smart sprinkler system uses approximately 6 gallons per minute per head when spraying about 30 feet.
For an inch of water, you'd run pop-up sprinklers for 30 to 40 minutes and rotating sprinklers for 60 to 90 minutes, split up over the course of a week. The problem is that factors like flow rate, water pressure, and sprinkler pattern/overlap all conspire to make figures inaccurate.
According to lawn care experts, the best time to water grass is in the early morning, ideally before 10am. During this time, the temperature outside is still relatively cool, and the wind and sun are less intense.
To make sure your lawn is getting enough water, place empty tuna cans in the areas you are watering and stop when they fill to 1-1.5 inches. (Alternatively, you can buy a permanent rain gauge to monitor precipitation or test your watering.) This can take 15-30 minutes, depending on what you use to water.
Approximate Running Time: To provide your lawn with 1 inch of water per week, run your spray sprinklers for about 2 hours weekly, ideally split into three 20-minute sessions in early mornings.
If the soil is dry an inch beneath the surface, your garden probably needs watering. We also find it helpful to keep the following watering formula in mind: 1 inch of water per 1 square foot = 0.62 gallons.
Turf studies show that most lawns only require irrigation once every 4 to 8 days to stay healthy and green. Shallow rooted plants result from irrigating every day. Irrigating less often and applying more water per irrigation results in deeper rooted plants and a healthier turf.
A typical lawn needs about an inch of water per week, equating to two 30-minute watering sessions.
Did you know that a broken sprinkler head can waste 25,000 gallons of water in six months!? All that water can fill a hot tub…more than 130 times. Remember to inspect sprinkler heads and aim them toward your landscape, not the sidewalk.
Sprinklers should be set to run for about 30 to 35 minutes at a time twice a week. Your goal is at least 1″ of water a week for your lawn.
Water Wisely
Most lawns need to be watered no more than three days a week in the spring as well as in the summer and two days a week in the fall. This watering schedule is recommended under normal water supply conditions.
It's best to run your sprinklers 2 to 3 times per week. Running them in the morning allows the lawn to absorb the most water. It's best to run your sprinklers only to the point where your lawn has 1 to 1-and-a-half inches of water. Newly seeded or sodded lawns need a light misting 1 to 2 times per day.