When Is the Best Time to Water My Grass?

Tired of unclear answers to your straightforward questions? Here's some straight talk that will get you the most perfectly watered lawn on the block.

The amount of water your lawn actually needs depends on a mix of factors including grass type(s), sun and shade conditions, soil composition and the time of year. Strike the right balance for your personal green space by factoring in your yard’s special considerations.

When Should I Water My Grass?

Timing is important when it comes to watering your grass. You’ll save water (and money) and have a better looking lawn if you water at the right times.

Time of Day

Grass and other plants in your yard should be watered early in the morning to get the most bang for your watering buck, according to Bob Mann, lawn and landscape expert for the National Association of Landscape Professionals (NALP). If you water in the heat of the day, much of it will evaporate rather than hydrate your lawn. If you water in the evening or overnight, the moisture will encourage the growth of harmful fungi.

Time of Year

Grasses should be watered in the warm seasons or summer months, Mann says. When the temperature is cooler, water less.

In the winter, grass goes dormant and doesn’t require watering. “If you maintain your lawn during the warm months with proper watering, mowing, aerating and fertilizing, your grass should be strong enough to withstand the winter and grow back strong in the spring,” Mann says.

How Much Water Does My Grass Need?

Generally, grass needs one- to 1-1/2-in. of water each week, whether from natural rainfall or watering. This amount can rise in extremely hot, dry weather and decrease when the temperature is cooler.

For How Long and How Often Does Grass Need to Be Watered?

Water your grass until there is one- to 1-1/2-in. of water in a rain gauge placed in the lawn where you are watering. Do this once per week. High activity areas will require more water.

“The principal hydrozone is the area of your lawn where there is the most activity and therefore will require the most water, such as your backyard,” Mann explains. “High traffic areas should receive routine weekly watering, and areas that are visually important to your lawn but don’t have much activity should receive reduced irrigation.”

Mann adds that minimal hydrozones are the areas of the yard that receive little or no human use. Those should be watered only if they start to look dry because natural rainfall should be enough.

The Lawn Institute also advises that the healthiest lawns are watered thoroughly at infrequent intervals. “Professionals recommend a deep watering compared to daily watering because it’s more efficient,” says Mann. “Most lawns are able to sustain five to seven days between watering, so if you deeply water on a weekly basis, your grass should thrive.”

If you notice that water is puddling or runoff occurs, turn the sprinkler off for a few minutes so that the water can soak into the ground. Allow the grass and soil to completely dry out before watering again.

How to Know When Grass Needs Water

If your lawn is getting one to 1-1/2-in. of water per week, it will likely remain healthy.

Two surefire signs that your grass needs more water than it’s getting:

Soil Probe Test. According to The Lawn Institute, if a probe such as an old screwdriver or large metal spike can easily be pushed into the soil, the soil is still moist and the grass doesn’t need watering. “Water only when the probe is difficult to push into the ground, or shows that the soil is dry at a depth of four to six inches,” according to the institute.

Grass Color. Grass that needs to be watered will have a gray-blue cast to it. On an adequately-watered lawn, footprints will disappear within minutes. If they can still be seen after 30 minutes or more, your lawn needs water.

Benefits of Watering Grass

One obvious benefit of watering your grass is beauty; a lush, green lawn looks much better than a dry, brown lawn. And a healthy lawn requires less effort to control weeds and insects. The benefits continue, Mann says: “Healthy lawns also act as natural coolants, noise minimizers, and play vital roles in cleaning the air.”

Susan B. Barnes
Susan B. Barnes has nearly 19 years of professional travel and lifestyle writing experience, with recent bylines in Allrecipes.com, Delta Sky, American Way, CNTraveler.com, Garden & Gun, Global Traveler, World Nomads, Gulfshore Life, Southwest: The Magazine, AARP.org and Go Escape Gulf Coast. She has previously written for Food & Wine and Southern Living, too.