How Often to Water New Grass Seed?

It’s very common to wonder how often to water new grass seed and how much water you need to use each time. Sometimes you can get this information from the dealer you buy your grass seed from and sometimes there is guidance on the packaging. Often this information is unclear.

How Often to Water New Grass Seed?

New grass seed should get at least 1″ of water each day. This can be done all at once. It doesn’t matter what type of grass seed you have. Even grass plugs and new sod need at least 1″ of water each day, or more.

In hotter and dryer locations, you may even need to give your new grass seeds 1″ of water twice a day or split this up into half an inch 3 to 4 times per day to ensure that the water is being absorbed and creating the proper germination conditions.

The Factors That Decide How Often to Water New Grass Seed

The following 5 factors can greatly increase how frequently you need to water your grass seed or seedlings.

Heat

High heat leads to higher soil temperatures and faster evaporation. The hotter it is, the more frequently you may need to water your grass seed to keep it in the sweet spot for germination. This is especially true for cool-season grass seeds.

Sun/Shade

The more sunlight an area is exposed to, the more often it will need to be watered. That is unless it’s early in a cool season and the ground is already at or below the recommended germination temperature for your grass type.

If you have both sun and shade in equal quantities in your yard, you may notice that the shady area holds more moisture. Attempt to water this part of the yard less to prevent pooling or overwatering.

Rain

Rain counts toward your lawn’s daily water consumption and may reduce the amount of water you need to add in the following days. After rain, check to see how deep the moisture has been retained. If there is standing water, you do not need to add more until this volume of water depletes itself.

Humidity

High humidity means there is more moisture in the air and water will not evaporate from the ground as quickly. Low humidity means that it will evaporate faster, especially in high heat. On low humidity days, you may need to water the lawn more frequently to keep it evenly moist.

Wind

Wind causes the ground to dry out and may disturb newly planted grass seed. The good news is that periods of wind typically follow periods of rain. However, when they don’t, special attention may need to be given to the moisture levels of the ground to ensure that your grass seed remains in place. Even small seedlings can be uprooted during a strong wind. Proper water levels in the soil can help keep them where they are.

How Often and How Long to Water New Grass Seed

The general rule is to keep the grass seeds damp until they germinate. Often this is done by watering just once in the morning to a depth of 1″ for cool-season grasses planted in early spring or split up into 2 or 3 watering sessions of 1/2″ each for warm-season grasses planted in any season.

Before Planting the Seeds

An often overlooked step when it comes to planting new grass seed is bulking up the moisture content of the soil before planting. 2 to 3 days before planting, watering the would-be lawn for 20 to 30 minutes or to a depth of 6 or so inches can help the ground retain moisture during the first week or so of the growing process. This step is especially important for any grass type that prefers warm soil rather than hot soil for germination.

During the Germination Period

During the germination period, the time when the seeds are turning into seedlings, the ground should be kept damp to a depth of 1″. This typically results from a light watering for just 5 to 10 minutes, depending on how well your soil retains water. In hotter weather, wind, or full sun, this may need to be done several times a day. This period should last 1 to 3 weeks, depending on the weather and grass type.

After Seedlings Sprout

Once seedlings begin to appear, you should follow this same procedure for up to 4 more weeks or until these seedlings are about 2″ tall. At this point, the seedlings should be watered for 20 to 30 minutes just twice a week. This will encourage root growth.

Never Water Your Lawn at Night

Even if you missed the chance to water your lawn during the day, do not attempt to make up for it by watering your lawn at night. Wait until the first dew appears in the morning or until sunrise. Watering a lawn at night, especially if your lawn is in the seed or seedling stage, can easily lead to fungal infection or cause seeds to mold before they germinate.

How to Water New Grass Seed

While it’s easy to overlook when you begin the project of seeding a new lawn, lives get busy. Before you know it, you may have missed a day of watering your grass seeds or seedlings. By having systems in place before you seed, you can save yourself the trouble of patchy germination or an uneven spread of seeds.

Sprinklers on a timer are the easiest way to keep your lawn appropriately wet all day with no lapse in coverage. Even better, you can set sprinklers in place so that you don’t have to set foot on your new grass seeds or seedlings.

Whether you’re watering manually or with a sprinkler system, test to ensure that you can use the same path each day and try to use a light spray or mist so you don’t disturb the grass seeds. Some overlap is okay, but you do want to ensure that you water the lawn as evenly as possible.

How Often to Water Specific Grass and Grass Seeds

Not all grass seeds will need the same treatment. However, in all cases, the important thing to remember is that grass seeds should be kept slightly wet and seedlings should be kept moist during their entire growing period.

How Often to Water New Bermuda Grass Seed

Bermuda grass seeds should be watered each day to a depth of 1″. This often only takes about 10 minutes. In hotter conditions, this should be broken up into 2 to 4 stages of watering, with about 1/4″ of water or just 5 minutes of watering time each stage.

How Often to Water New Fescue Grass Seed

Fescue grass seeds should be kept wet during the entire germination period. Often this is done by providing about 10 minutes of water first thing in the morning each day. Like all seed types, however, in hotter or windy weather this should be split up into 2 to 4 stages of watering for about 3 to 5 minutes each time.

How Often to Water New Ryegrass Seed

Ryegrass seed should be watered to a depth of 1″ at least once per day. However, if the soil appears to be drying out, it may be a good idea to schedule additional watering periods or break up this single watering session into several 5 minutes or 1/2″ sessions throughout the day.

How Often to Water New Kentucky Bluegrass Seed

Given where Kentucky Bluegrass thrives and how early in the year it can be seeded, this grass type should only need one watering session each day or, in very dry weather or wind, two sessions. A single session should last 5 to 10 minutes, depending on how wet the area was when the session began.