Last Updated on March 2, 2023 by Mattias
The overseeding is a process of sowing new seeds directly into existing grass without tearing up the lawn or the soil.
It’s an easy way to help fill in bare spots, enhance turf density, create improved grass varieties, and improve your lawn’s color. Watering your green lawn at the correct times is essential, and adequate moisture needs to be under the roots up to 2-3 inches deep.
If you are stressing about watering your lawn right, here are a few top tips that you must know about how to water grass in a new lawn after overseeding.
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How Long to Water Overseeded Lawn?

Once you have overseeded or aerated your lawn during the early fall, you must follow up with proper watering.
To save you from guessing your lawn’s needs, we’ve gathered details on how long, when, and how to water the grass after aeration and overseeding. It includes:
Before Germination
Germination is a natural process by which plants grow from new seedlings. Before the grass seed germinates, for best results, follow the guideline, “less water but more frequently.”
The germination process may take about 7 to 21 days based on the nutrient levels, type of grass, and soil temperatures.
This method aims to keep the seeds moist before they germinate. It may indicate watering about two to three times a day but doing it for a shorter period, around 15-20 minutes, in areas of your lawn.
Four to Five Weeks After Germination
Following germination, you may want to water your grass less frequently but with more water (this time: “more water, less frequently”).
The technique is to soak the soil to a depth of about 2-3 inches. It means using sprinklers thrice weekly for around 45-60 minutes in each area.
Soil moisture at a much deeper level promotes deeper root development. If the soil is only damp from the top, you’ll get stuck with shallow roots in the first inch of the soil.
Place tuna cans in different lawn spots to monitor how much water your grass is getting. You need to get about one inch of water every time you water for around three inches a week.
You can also try a rain gauge to measure natural rainfall and adjust your watering schedule accordingly.
Five Weeks to Nine Months After Germination
With time, water the lawn so it receives two inches of water every week.
Even though you may have a green lawn that is properly established, it takes time for the root system to mature completely. That is why it’s crucial to regularly water your grass, which means watering once or twice weekly if there isn’t enough rainfall.
A new lawn is more prone to drought damage in its first year. It’s typical for people to seed large areas of their lawn in the fall and get them thin or die back in early summer if it doesn’t rain for weeks or more.
How to Water your Lawn After Overseeding, Aeration, or Power Seeding

The lawn’s watering requirements immediately after proper overseeding and aeration may differ from what you might have previously done.
Your lawn will need more frequent watering but in a lesser amount. Also, you must keep the soil moist but may want to water it briefly. It generally means watering twice every day but for a short period.
While you can accomplish that by hand-watering, such as by dragging a hose and sprinkler around, there’re homeowners with an irrigation system who can naturally maintain their lawn’s proper watering needs.
It only takes the guesswork out of that process when you may have a “set it and forget it” mindset with your irrigation system.
Specific advanced irrigation systems also contain technology like rain sensors which consider the amount of water your lawn is already getting from mother nature and adjust it as needed.
When to Water After Overseed your Lawn?
Proper watering after you overseed your lawn is crucial in enabling the seeds to germinate and the growth of the grass in the lawn.
To get great results, follow these effective watering methods.
- Water the overseeded area properly for at least half an hour. It will allow the seed to wash deep into the soil;
- For one week, water your lawn around three times daily;
- For the second week, water the lawn around two times daily and;
- For the third week watering once every day is enough;
- Coming to fourth-week watering once after two days is adequate;
- Once the grass is established, you can water it once or twice weekly.
The germination process usually occurs in about two to three weeks, according to the soil and watering techniques followed. You must see small weeds growing along the grass, so always be prepared to eliminate them.
The best time to remove these small weeds is in the early stages.
How Much to Water your Lawn After Overseeding?
Always ensure that the soil in your lawn is thoroughly soaked in the root zone. It indicates soaking your ground, so the grassroots reach 3 inches deep.
You can check its depth by digging up a tiny core of turf and soil and notice how far the water has reached into the soil.
You must check that after 24 hours of watering your lawn. Also, you can increase the watering time if you’ve noticed that not much water has reached the depth you want. The intervals of watering your lawn depend on the rainfall and soil type.
I recommend using a soil tester since it’s the best tool to know your soil type and perform the watering after overseeding the grass.
What Equipment Do You Need to Use for Watering After Overseeding?

Most people use water cans or hoses for watering their lawns. However, it is not advisable to use a water can or hose.
The best way to provide enough water to your grass is to use a sprinkler system that gives constant soaking. The result of sprinklers may vary. But, a typical sprinkler can put on adequate water if left in every desired spot.
Using a sprinkler system ensures your lawn always gets the right amounts of water. I always recommend using a sprinkler system during the summer heat since it can save your lawn from the burning sun.
How Long to Water Overseeded Lawn Summary
I hope you liked this article about how long you must water an overseeded lawn. As you discovered, there are many aspects to consider, and by following this guide, you can get a good-looking green lawn.
Did you find this article helpful? Share it with your fellow lawn owners and help them get a healthy lawn!
Meet Mattias Jonsson, the head of content at RainSaucers. Passionate about gardening and water-related topics, he’s dedicated to providing expert information and resources to help improve your home, health, and wallet. Learn from his research and experience.