This chapter will outline your lawn’s relationship with water. Water makes up 70 to 80 percent of the weight of our turfgrass lawns and the clippings alone are nearly 90 percent water. It is wise to take the time to understand the reasons a turfgrass lawn requires varying doses of hydration during different stages of development and seasons. Once you increase your awareness of the factors that affect your turfgrass, your ability to competently care for your yard will be heightened and you are well on your way to Learning your Lawn!
New Turfgrass Sod
Newly installed turfgrass sod has very crucial watering needs. These water requirements will be much higher in the beginning than they will be after your lawn is established. In the previous chapter, we recommended watering prior to sod installation so that the soil is moist 6-8 inches below the surface. Proper watering immediately after installation will maintain that moisture level. This care will impact the lawn’s capacity to flourish for years to come.
Apply 1 inch of water as sod is being installed.
Daily Watering Times For New Sod
| Week | 1st | 2nd | 3rd | 4th |
| How often to water | Every Day | Every Other Day | Every Third Day | Every Fourth Day |
| April | * | * | * | * |
| May | * | 1/3 | 1/2 | 2/3 |
| June | 1/4 | 1/2 | 2/3 | 3/4 |
| July | 1/4 | 1/2 | 3/4 | 1 |
| August | 1/4 | 1/2 | 2/3 | 3/4 |
| September | * | 1/3 | 1/2 | 2/3 |
| October | * | * | * | * |
If watering multiple times per day schedule watering at the following times:
3 times daily – 6 p.m., Midnight, 6a.m.
2 times daily – 6 p.m., 2 a.m.
Once daily – 5-6 a.m.
Keep the sod and soil moist for two weeks and up to 1 month
The First Week
Water is your new lawn’s best friend. New sod should be kept moist for approximately two weeks. This moisture will allow the roots to burrow down into the soil. However, do not leave the sod soaking in water. Soil should be moist but not saturated. Saturation impedes airflow and will reduce root growth. Water application will depend on temperature, wind, reflected heat, and other factors. Learn your Lawn!
A great way to check to make sure your soil is receptive to root growth is to pull back a corner of the turf and push a screwdriver or other sharp tool into the ground. The tool should penetrate easily into the moist soil 6 to 8 inches. If it doesn’t, more water is needed.
Regardless of the type of sprinkling system you use, be certain that water reaches all the areas of your new lawn. Corners and edges are easily missed by sprinklers and are particularly vulnerable to quickly drying out. Additionally, sod sections near buildings may require extra water if you notice turfgrass drying out faster due to reflected heat.
Sometimes, an application of water needs time to soak into the soil. Runoff may occur on some soils and sloped areas before the soil is adequately moist. In this case, you may need to stagger your water applications. To conserve water and ensure adequate soak-in, pay attention and turn the water off prior to runoff. Wait 30 minutes to an hour and restart the water in the same area. Repeat this process until the proper soil moisture is achieved. In hot weather, sod may need to be watered around 1/8” 3 times a day during the first week.
The Second Week
Weather will largely determine the quantity of water and frequency of applications during the second week. The soil needs to continue to be kept moist 6 to 8 inches below the surface. In cooler temperatures, watering every other day or every third day usually accomplishes this. Hot, dry or windy conditions will result in higher hydration needs. Water 1/8” twice daily during the second week if high temperatures persist. In addition to these regular waterings, you can always refresh and cool your lawn with a light sprinkling of water during extreme heat.
As the turf starts to knit its new roots into the soil, pulling back a corner of the turfgrass sod to test soil moisture will be harmful to the lawn. But, you can still test the soil by pushing a screw driver into the turf and checking for moisture. If the first 6 to 8 inches of the soil are not moist, the lawn needs to be watered. Learn you Lawn!
The Third Week
You can scale back your watering routine during the third week of having new turfgrass. In cooler climes, you can wait an extra day between watering. Water 1/8 – ¼” daily if high temperatures remain.
The optimal time of day to water is early in the morning for several reasons. The turfgrass daily growing cycle begins early in the morning. Mornings typically have lower wind speeds and lower air temperatures giving soil a better chance to soak up the water. Observing your lawn closely will clue you in your lawn’s needs. Usually, one area of your lawn will turn a blue gray color before the rest of the lawn. When this condition appears, your turfgrass is thirsty. Apply 1” of water to the entire lawn.
The Fourth Week
During the fourth week, continue watering your new lawn. Wait an extra day between waterings. Going forward, you should cut back one day between watering each week until you are watering only once a week. Follow the watering guide on page 32 to conserve water.
Summer Watering
During the summer, most lawns remain vibrant green with 1 to 1.5 inches of water a week (after they are well established) This water can come either from sprinklers or from rainfall. As long as water is applied evenly and saturates the underlying soil, that is all that is required for proper lawn health.
Studies indicate that only 19 to 23 inches of applied water is needed to keep an established lawn green all summer long. Proper mowing and fertilizing will also conserve water.
Allowing a bluegrass lawn to go dormant (usually after 1 year of growth) in the summer is acceptable during seasons of extreme drought after the turf is well established. See the section below on summer dormancy to learn how to “brown out” your lawn.
Watering Tips
Many people over-water their lawns because they are overly concerned about their turfgrass dying. Learn your Lawn! It is hardier than you might expect. Sadly, a lot of water is wasted and many lawns are damaged or destroyed by over-watering. The mistake most homeowners make is that they “set it and forget it.” Automatic sprinkler systems need to be adjusted as weather and the seasons change.
Apply the Same Amount of Water Each Time
The best way to water is to apply the same amount of water every time the sprinklers come on. The adjustment you will be making is how often you water. Think of the soil under the turfgrass as an in-ground reservoir. When the sprinklers come on, the reservoir in the soil will fill. After the sprinklers turn off, the turfgrass roots will utilize the water from the in-ground reservoir. This approach will promote deep root growth.
Deep roots are important to great lawns. Having a deep root zone will mean you will need to water less frequently. In the Spring you may only need to water every 10 days and then increase your watering cycles to once every 6-7 days during the heat of the summer. Once you lawn is established, follow the watering guide on page 32 to keep supplemental water less than 24 inches per year.
If possible, have your sprinkler system designed for windy conditions. When planting a landscape, avoid placing plants in front of sprinkler heads because spray patterns will be distorted. A drip or low volume system is a good alternative in shrub or flower beds. Inspect the system after each use for effectiveness, and check for damaged or displaced sprinkler heads at least once a month. Regularly check for broken heads, or heads that are not popping up or spraying properly. Explore using Mammoth Gripper head stabilizers in your system.
Apply Water Evenly in Specific Use Zones
An important aspect of a sprinkling system is to apply water as evenly as possible. If a system is not designed properly, there will be areas of the lawn that receive more water than others. Poorly designed systems will also cause the reservoir in some areas of the soil to be lacking and will result in dry spots. If you have dry spots, either add a head to your sprinkler system or use a hose end sprinkler to water that spot. Do not turn on your sprinkler system more often or run it for longer times to get rid of dry spots. This is a major misuse of water.
Soil Moisture and Envirotranspiration (E.T.) Sensors
Conscientious gardeners will learn to read their plants and lawns and apply supplemental water only when needed. Smart technology is available to detect dry conditions and prompt sprinkler systems to water the landscape. In-ground soil moisture sensors and envirotranspiration (E.T.) sensors are available for this purpose. Most nurseries and sprinkler supply outlets sell these sensors. Rebates may even be available for those who choose to utilize these modern technologies.
Finding the Application Rate
To find out how much water each station applies in a given period of time, set tuna cans or catch cups throughout your lawn. These cups can also be used to find out how uniformly the system applies water. A more uniform system saves water and promotes a healthier lawn. Catch cups are available through the USU Extension Service.
Define each station’s irrigation zone (the area watered by the station). Place the cups in the irrigation zone. For zones that overlap, place cups between the heads of the different zones and run the zone being tested and the overlapping zone for the same amount of time. Run the station for 5 to 25 minutes to determine how long it takes to fill the can. Note the amount of water in each catch container. If the readings are not close to being even, then the sprinkling system should be adjusted.
Calculate the Run Time
Using the catch cup method, you can determine the time required to apply one half inch of water. If runoff occurs when filling the cups to the one-half inch line, try using several start times. Divide the run time by the number of start times to determine the adjusted run time.
Adjusted run time = Run time/Number of start times
Once you have calculated the time required to apply one-half inch of water to a particular station, you can double or triple the run time in order to apply the recommended 1”-1.5” every time you water. Now you know how many minutes to program your automatic controller to run. Or, if you are using a hose end sprinkler, you know you long to set the reminder timer. Repeat these steps for each station.
See the watering chart below for frequency to find how many minutes to set the controller use the following formula.
Watering Minutes = (amount of water applied in 1 hour) / 60
Watering in Utah
A typical northern or central Utah lawn has a water demand curve that begins in mid-April, rises to a peak in July, and then falls rapidly until mid-October. Lawns in southern Utah have a different demand curve. Adjusting your times monthly to better follow this demand curve will save you water and money. An easy way to do this is to keep the minute constant and increase or decrease the number of days between watering as shown in the table above.
Follow the watering chart below for an established lawn. Deeper/longer watering will promote a more robust root system which can draw from a larger water table. This watering chart is for cool season grasses with a climate similar to that of Northern/Central Utah.
Northern/Central Utah Watering Chart
| April | No Irrigation recommended, unless needed under extremely dry periods |
| May | 1 inch every 10-14 days |
| June | 1 inch every 7-10 days |
| July | 1 inch every 6-7 days |
| August | 1 inch every 6-7 days |
| September | 1 inch every 7-10 days |
| October | 1 inch every 10-14 days. A good soaking to a depth of 6-8″ around the middle of the month. |
| Novmeber | No irrigation recommended |
Stressing Your Turfgrass Lawn
Ever heard the expression, “What doesn’t kill you makes you stronger”? If you want to make your turfgrass lawn hardier, try stressing it out! Once your lawn is established, don’t stress yourself out by thinking you have to stick to a rigid schedule. By going an extra day or two without water, you are promoting deeper root growth. The deeper the roots are allowed to penetrate the soil, the better the overall health of your lawn. Roots will only grow as far as they need to in order to get water. If you are always giving them water up near the surface of the lawn, the roots have no incentive to grow deeper. You can easily check your watering depth by using a soil probe or screwdriver.
Chanshare Farms recommends waiting as late in the Spring as possible to begin a watering routine. The longer you wait, the healthier your lawn will be in the summer months. And don’t worry. Killing your bluegrass lawn by extending periods of time between watering is virtually impossible. The lawn may turn brown in some areas, but it’s just the turfgrass plant going dormant, not dying. Adding water in a timely manner will make that golden brown spot spring back to life. Learn your Lawn!
Always keep an eye on the weather forecast. If you see that significant rain is coming, do not water your lawn! If you “set it and forget it”, there will likely be times when your sprinklers waste water by spraying in the middle of a rain storm.
Summer Dormancy – Browning Out Your Lawn
Browning out your lawn in the heat of the summer, when temperatures climb to over 90 degrees F, can create a more resilient lawn. A bluegrass lawn can survive on 1/2″ of water for about 4 to 6 weeks. Cutting water for that length of time and then resuming a regular watering schedule can force the plants to drive their roots deeper into the soil in search of water. The grass plants will stop producing clorophyll and focus all their energy on preserving their roots as a survival tactic. Follow these steps if you want to brown out your lawn.
- Do not fertilize for at least 4 weeks before browning out your lawn.
- Do not mow for at least a week before cutting the water.
- Stop irrigation for 4 to 6 weeks. Do not let the lawn go dormant more than once a season. Bringing the lawn in and out of dormancy will weaken the plant and allow weeds an opportunity to grow.
- Hand weed while you are allowing the lawn to brown out. Do not use herbicides during this time.
- When you begin watering again make sure you are watering deeply and infrequently. You can use a slow release fertilizer once you have started watering again to promote a quicker green up.