A lush lawn carpeted with thick grass can be the envy of the neighborhood. It is not only attractive but also an area of the yard that will be bristling with activity. We cut across the lawn to get to the mailbox. Our children play on the lawn, as do our pets. Only a healthy lawn can stand up to all that activity.

So try to get your lawn off to a healthy start. When you start a new lawn from seed (or improve an existing one by overseeding it), proper watering will be key to success. In this article you will learn how often you should water new grass seed.

How Much and How Long to Water New Grass Seed

How much and how long you water new grass seed will depend on whether you are overseeding an existing lawn or starting a whole new lawn from scratch.

Generally, you should give the grass seed you have sown to start a new lawn from scratch 3 to 4 inches of water per week. Grass seed used to overseed a lawn should be watered about 1 to 2 inches per week.

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Overseeding

Why overseed a healthy lawn? Overseeding gives you a thicker lawn. The more thickly your grass grows, the better chance you have of crowding out weeds.

Try to overseed one to two times per year. Run the mower over your lawn first, cutting the lawn a little shorter (1.5 to 2 inches tall) than normal.

Grass seed used to overseed an existing lawn should be watered less than seed used to start a brand new one: 1 to 2 inches per week. If you furnish more water than that, you risk overwatering the existing grass.

Moreover, such seed will not need as much water, because the existing grass will shade it some. Water a couple of times a day rather than all at once so that the soil stays evenly moist.

New Lawn (Reseeding)

When establishing a new lawn, the biggest part of the job is soil preparation. Providing proper drainage and nutrients is part of that preparation, but so is watering. You might wonder why you are watering soil that does not even have anything planted in it yet.

But grass seed will sprout better and faster in soil that has been pre-moistened. So as part of your soil preparation, gently water the soil with the spray nozzle of your hose. Your goal is to make at least the top 3 inches of soil evenly moist. Do not overwater.

After sowing the grass seed, give it 3 to 4 inches of water per week. Initially, it is better to achieve this amount by watering two or three times a day, rather than by doing a lot of watering at any one time.

By distributing the irrigation, you avoid overwatering, which is as bad as underwatering. But after germination, start irrigating less often, providing more water each time.  

Temperature and Humidity Considerations

Maintain some flexibility in your approach to watering grass seed used to start a new lawn, because different conditions call for different amounts of water.

Temperature and humidity, for example, must be factored in when deciding how much water new grass seed needs. More water (about 4 inches of water per week) will be required in conditions that are hot and dry.

Less water (about 3 inches of water per week) will be needed in conditions that are cool and humid. In fact, weather conditions should always be considered when watering your lawn, whether it’s a new one or an existing one.

Common Mistakes When Watering New Grass Seed

There are a few mistakes commonly made by people who have just sown grass seed for the first time:

• Not watering enough: A lack of water will cause your grass seed to dry up.
• Watering too much: Excessive water can actually rot the grass seed. This is why you have to take the weather into consideration. When you irrigate at a time when the ground is already moist (after a heavy rain, for example), the result is a waterlogged soil.
• Improper watering schedule: Distributing the irrigation throughout the week is good, but excessive distribution can lead to shallow root development. Strike a balance.