How Long to Water Your Lawn

Watering is one of the main things when it comes to taking care of your lawn. But watering isn’t as simple as setting up a sprinkler system. Water too little and your lawn will become dry and patchy. Water too much and your lawn may fall victim to rot or disease.

Luckily, This Old House has created a guide to watering your lawn, teaching you how long to water, how often to water, and more. Read these tips to find out the best way to keep your lawn hardy, healthy, and hydrated.

This Old House Reviews Team recommends hiring a lawn care company like TruGreen. With five annual plans and many a la carte services, TruGreen can keep your lawn lush.

How Long Should I Water The Lawn?

You should water your lawn once or twice a week, giving your grass 1 to 1.5 inches of water each time. The precise number of minutes for each watering will vary from lawn to lawn, depending on factors like the size of your lawn, the type of sprinkler you have, and its settings.

Here are a few methods for finding the number of minutes you should water your lawn.

• Do a can test: Tuna cans are 1 inch tall, and work best for this method. Empty one out, and set it in an area that your sprinkler hits. Turn your sprinkler on, and check the can periodically to see how long it takes to get ½ of an inch of water in there. You can use that to find how many minutes you need to water either once or twice a week.
• Break it down mathematically: Your sprinkler system will have a designated flow rate of gallons per minute, which you can find out from the manufacturer. To find out the number of minutes to run your sprinkler, multiply your lawn’s square footage by 0.62 gallons—which is 1 inch of water per square foot—then divide that total by the sprinkler flow rate.
• Look at a flow timer: You’ll need a timer that measures flow in hundreds of gallons. Multiply the square footage of your lawn by 0.62 gallons, and that will tell you how many gallons you need to give your lawn the water it needs.

How Much to Water Your Lawn

Watering the proper amount is critical—overdo it, and your grass, your water bill, and the environment will suffer. The amount of water you need is generally 1 to 1.5 inches per week, but it can vary depending on your grass type, the climate you live in, your soil type, and the age of your lawn.

Established Lawns

In general, you want the top 6-8 inches of soil to be moist, but not soggy—which translates to 1 to 1.5 inches per week. Watering deeply, but infrequently, leads to stronger root development and drought-resistance than watering briefly every day. You can break up these waterings into twice a week during most of the year, or three times a week during the hot summer months.

Newly Seeded or Sodded Lawns

To encourage proper growth, newly seeded or sodded lawns need moisture in the top inch of their soil, but not so much that they turn soggy. Instead of watering a few times a week, you will need to take a mister and gently spray the newly seeded areas once to two times a day, depending on the weather.

As the seeds germinate, keep the top 2 inches of soil moist. Once the grass grows to a 3-inch mowing height, you can reduce watering to twice a week. Then, you should soak the soil down 6-8 inches, like you would an established lawn.

Watering Cool vs. Warm Season Grasses

You need to care for different grass types in different ways to keep them at their healthiest and hardiest.

Cool Season Grasses

These types of grasses, like fescue, rye, and bluegrass, grow actively in the fall. They’ll need about 1-1.5 inches every week until the growing season ends, roughly when the first frost sets in. If you don’t water cool season grasses during a drought, they will go dormant but re-green when it starts raining again.

Warm Season Grasses

Warm season grasses, including bermuda, St. Augustine, zoysia, and centipede grass, do most of their growing in the summertime. Overall, they require less water than cool season grasses, but even they need extra water in the dead heat.

Best Time of Day to Water Your Lawn

The best time to water your lawn is before 10 a.m., preferably between 4 a.m. and 6 a.m. At this cool time of day, it’s less likely the moisture will evaporate before your grassroots can absorb it from the soil.

If you can’t water before 10 a.m., don’t make the mistake of watering late at night. It may be cool then, but if the moisture sits on your grass overnight, it can make your lawn more prone to disease. The second-best time to water is between 4 p.m. and 6 p.m.

How to Tell if Your Grass Isn’t Getting Enough Water

There are several tell-tale signs that you need to water your lawn. It’s simple as can be, but if your once-vibrant green lawn has taken on a gray shade, you need to water. Curled grass blades are another indicator—it means your grass is thirsty.

If you’re unsure, consider tackling one of two tests. For the step test, simply walk on your lawn. If your lawn is well-watered, your grass should spring right back up where you’ve stepped. If it doesn’t, it’s lacking moisture, so it needs water.

The screwdriver test is another classic. See if you can drive a long-bladed screwdriver 6 inches into the soil. If you can’t push the tool down that far or you meet a lot of resistance, it’s time to water.

Watering Your Lawn Automatically

There are many different ways to efficiently and automatically water your lawn. There are a few factors you should take into account. Ask yourself the following questions: How much water will I need? How large an area do I need to cover? What shape is my lawn? Is there anything nearby that can’t get wet?

Here are a few popular types of sprinklers to consider:

• In-ground sprinklers – These systems can be expensive, but are highly efficient. The sprinkler heads pop up automatically to water, and pop right back down when the watering is done, delivering a precise amount of water.
• Pulsating sprinklers – This type shoots out water horizontally in a powerful stream, covering a large area easily. Grassroots get the level of moisture they need quickly. However, the pulsing might be too intense for newly seeded or sodded lawns.
• Oscillating sprinklers – These are a good alternative for newly seeded lawns, since the force of the water is weaker, and you still get good coverage.
• Hose-end sprinklers – These traditional sprinklers are the most common and come in many different types.

Make sure your automatic sprinkler is doing its job, when it needs to do its job. If the forecast calls for a lot of rain, adjust the settings accordingly. Also, make sure it isn’t pointed at the street—you don’t want to soak any passersby.

Professional Lawn Care

Your investment in your lawn shouldn’t stop at proper watering techniques. You’ll also want to make sure your lawn is properly fertilized, aerated, and overseeded as needed, and that it gets regular weed and pest control. The easiest, most efficient way to do that is by hiring a professional lawn care company.

This Old House Reviews Team recommends TruGreen, a lawn care provider that offers five annual plans, a wide range of a la carte services, and highly trained technicians. TruGreen is available in every state except for Alaska.

Our Rating Methodology

The This Old House Reviews Team backs up our lawn recommendations with a detailed rating methodology that we use to objectively score each provider. We review lawn care plans and packages, navigate the provider website and speak with customer service representatives, request quotes, and analyze customer reviews for each provider. We then score the provider against our review standards for plan options, additional benefits and customizability, availability, trustworthiness, and customer service to arrive at a final score out of 100.

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