How Much Water Does My Lawn Need?

A Guide to Watering Smart - Even During a Drought
How Much To Water Lawn

You already know that water is essential for maintaining a healthy lawn. But how do you know how much water your lawn actually needs? Here in Kansas, this question is more complicated by the heat, wind and humidity our state is known for – not to mention the recent drought. As a trusted lawn maintenance company in Wichita, KS, Elite Landscape Solutions has provided this guide to help you figure out the ideal watering schedule to keep your grass lush while conserving water and keeping your water bill down.

How Much to Water Your Lawn

Established Lawns

On average, an established lawn needs 1 inch – 1.5 inches  of water per week, including rainfall. The goal is to get the top 6-8 inches of soil damp but not soggy. Here in the Wichita area, you may find that you need an extra watering session during summer when the heat is at its worst.

Newly Seeded or Sodded Lawns

It’s important not to over-water new sod or a newly-seeded lawn. The top inch of soil needs to be kept moist but not soggy. For new seed, a light daily misting is needed until the seeds germinate, and then switch to longer daily watering sessions until the grass is long enough to mow, or about 3 inches tall. At that point, you can gradually switch to watering less often but continue watering deeply to maintain about an inch of water per week.

For new sod, start with 2-3 daily watering sessions for the first two weeks. Then switch to watering once or twice a day for a longer period for a couple of weeks. About 5 weeks after the sod is installed, change to watering every other day or every two days for a total of one inch of water per week. After about two months, the sod should be established and you can cut back to watering deeply once or twice a week.

How to Establish a Watering Schedule

Water Deeply and Infrequently

The general rule of thumb is to water deeply and infrequently to encourage deep root growth. Two 30-minute sessions per week is better than daily or every-other-day watering to encourage deeper root growth and improve heat and drought resistance. 

Remember, plant roots don’t just draw water out of the soil; they also need air to breathe. If the soil is saturated with moisture, the root system can’t get oxygen. Wait as long as possible between waterings to let the soil dry out so it can draw air in. This will give the roots oxygen to breathe under the ground. 

With a sprinkler system

Schedule one or two watering sessions per week of 30 minutes each per zone. This will water your lawn deeply and give it time to dry out between waterings. Your irrigation system should have posted flow rates that can help you determine whether your lawn is getting an inch of water each week.

Without automatic sprinklers

Consider investing in a hose-bib timer that can attach to your hose and automatically shut it off to avoid overwatering. You can use a rain gauge or a tuna can to measure how much water is applied during each watering session so you’ll know if your lawn is getting one inch per week.

Water Early in the Morning Before it Gets Hot

Knowing what time to water is just as important as knowing how much to water. Watering in the early morning will keep evaporation to a minimum and give the water a chance to soak into the soil. It’s often less windy at this time of day too, so more of the water will make it into the ground instead of just blowing across the grass blades.

Avoid Watering the Lawn in the Evening

Watering your lawn late in the day can lead to fungal diseases that will damage your grass. If you need to water more than once per day, schedule your second watering session for late afternoon, well before temperatures start to drop.

Factors that Affect the Amount of Water Your Lawn Needs

Soil type – Soils with a lot of sand will drain quickly so they may need to be watered more often. Clay soil holds onto moisture, so its better to water less often to prevent runoff.

Grass type – Warm season grasses like zoysia and Bermuda grass are more drought-resistant and need less water than cool-season grass like bluegrass or fescue.

Temperature – During the heat of summer, your lawn will lose more water due to evaporation. You may need to add an extra watering session or split your watering sessions during this time.

Wind – Try to avoid watering on windy days. Not only will much of the water blow away, but wind and heat also cause the water to evaporate quickly.

Shade vs Sun – Areas of your yard that get a lot of sun exposure will need more water than shady areas. If you have a sprinkler system, adjust the sprinkler zones in these areas to avoid overwatering or underwatering.

Rain – Remember that rainfall counts toward your lawn’s weekly watering needs, so don’t water when it rains. Consider adding a rain sensor to your sprinkler system to shut off the sprinklers during a rainstorm. Smart sprinkler controls are also available, which monitor the weather conditions and adjust your irrigation schedule accordingly.

How to Tell When Your Lawn Needs to Be Watered

The simplest way to tell if your lawn needs to be watered is to walk across it. This “footprint test” will show clear footprints in the sod if your lawn needs water. If you don’t see footprints, your lawn doesn’t need watering yet.

A more technical method for calculating when and how much to water is evapotranspiration (ET). ET is a measure of both evaporation (water released from the soil) and transpiration (water released from plants). Evapotranspiration takes into account the air temperature, wind speed, amount of precipitation and solar radiation, among other factors, to tell you how much water is lost from your lawn each day.

Here in Kansas, the K-State weather data library includes an evapotranspiration table that shows the ET of turfgrass. You can use it to check the amount of precipitation and ET. When we’ve lost about an inch of water, it’s time to water your lawn.

Signs of overwatering

  • Puddles of water in the grass
  • Mushrooms are growing in the lawn
  • Ground feels squishy when you walk across it
  • Grass is yellow or otherwise discolored

Signs of Underwatering

  • Brown or yellow patches in the lawn
  • You leave footprints or dents when you walk on the grass
  • The ends of the blades of grass start to curl
  • Grass blades look dull

Watering During a Drought

Wichita, like most of Kansas, experienced drought conditions in 2022 and 2023, along with periods of excessive heat in the summers. During a drought, it’s important to use weather data to determine how often to water your lawn. 

Kansasgreenyards.org is a good resource for more irrigation techniques to help conserve water. In a severe drought, you can save even more water (and money) by turning off your sprinklers and letting your lawn go dormant. Your lawn will turn brown when you stop watering, but once the rain returns, your grass will green up again.

Consider Hiring a Professional

Elite Landscape Solutions is an experienced landscaping company in Wichita, KS. We know the local weather conditions, soil types and commonly-used grasses, and we can design an efficient irrigation schedule to keep your lawn looking great all season long.