How Often to Water Grass Seed

Watering grass seed is essential for germination. Timing, frequency and weather conditions all play their part in the grass seed watering process. You should aim to water the soil before and right after seeding, according to a schedule.

Grass seed needs to be watered twice per day up to 10 minutes. The seed needs to be watered in the morning and the evening until they germinate. Once they root you only need to water the grass once per day for a healthy lawn.

Watering grass seed is also influenced by weather and seasons. The more it rains the less you need to water the grass seed. However, too much water can be as detrimental to grass seed as is insufficient water.

How often should grass seed be watered?

Grass seed doesn’t germinate when completely dry. It needs water to germinate and to lay roots to form a lawn. You need to water grass seed for a perfect turf.

The soil needs to be watered two to three days before seeding. Water penetration between six and eight inches is perfect for moist soil. Once the seed is in the soil watering is needed twice per day to depths of two inches.

To avoid unpleasant surprises you should always check water level penetration into the soil. This can be done using a screwdriver.

As long as you can easily push the screwdriver into the soil for eight inches before seeding, the soil is correctly watered and moist. You should also remember the soil needs to be moist, not soggy.

Once the seeding process has finished you should only water the first two inches of the top soil. The soil is ready when moist. Pooling water is a sign of over-watering and it should be avoided as it can kill grass seed even before germination.

Watering grass seed should always be planned according to the weather forecast. Rain influences the amount of watering you need to do for the grass seed to sprout.

Make sure to only water the grass seed on dry days and to water the soil for a few more minutes in case of a drought.

A step-by-step guide to grass seed watering

Watering grass seed is a long process. It takes anywhere between a few weeks or even more than a month for grass seed to germinate and start looking like a lawn. Daily watering is a must during this period. Here’s how to do it.

Grass seed-soil preparation

Humidity levels in the soil need to be considered before seeding. This is done by watering the soil at least a couple of days before seeding – there’s no need to do this if you’ve just had a couple of rainy days.

Puddling is to be avoided at all costs as it indicates a high humidity level which is not ideal for grass seed to grow roots. However, you should remember the soil needs to be maintained moist for turf to grow.

The soil can be watered once per day before seeding. Watering the soil in the morning is preferred to afternoon watering due to higher temperatures and evaporation.

Top tip: you should always aim to water sand-rich soils more. These soils tend to dry out quicker and they need extra watering before seeding.

Watering grass seed

Once the seeding has been completed you need to start watering the grass seed twice per day. Watering in the morning (before 10am) and in the evening (after 6pm) is ideal.

Avoid watering the grass seed when the temperature is at its highest as this could lead to premature water evaporation.

Sprinklers are ideal for watering grass seed twice per day for full germination and are especially useful when you need to water large areas of a lawn. You should avoid watering the grass seed directly from the water hose, without a sprinkler.

Top tip: make sure you check soil moisture levels daily. Puddling water means you might have to reduce the 10-minute watering sessions. However, these are normally not shorter than five minutes. A sprinkler with a timer can help.

Once seeding has been completed, water the grass seed twice a day

Watering grass seed post-germination

If you want to keep turf looking vibrant, watering is a constant effort, so you’ll need to keep on watering your lawn after germination.

How long does it take for grass seed to sprout? It normally takes anywhere between seven and 21 days for grass seed to sprout.

You need to water the grass seed twice per day during this time. You will then transition to watering the lawn once per day for up to one-inch soil penetration to maintain the lawn.

How much water is needed for grass seed to grow?

  • Soil preparation – 6-8 inches of water into the soil – once per day
  • After seeding – 2 inches of water in the soil – 2 times per day
  • After grass seedlings emerge – 1 inch of water – once per day

Top grass seed watering tips

Grass watering isn’t overly complicated when done correctly, but one of the most important things to take into account are local variables such as weather or types of grass seed.

Make sure to check moisture ranges for your grass seed

Each type of grass seed bag you buy comes with clear watering indications. Some types of grass seed might need more water while others might need less water.

For example, some Fescue grasses known as pasture grasses are resilient and have high drought resistance. This grass seed might not need as much water to sprout, and are ideal for those who don’t have time for watering the lawn twice per day.

Ensure constant soil moisture

The main objective when creating a new lawn is to ensure constant soil moisture. You cannot water the soil for more than one day to make up for a waterless day in the previous days.

Constant soil moisture is achieved by following a grass seed watering plan. This takes into account both the type of grass seed for the seeding and the type of soil you have around your house.

For example, hard Fescue grass seed are ideal in low fertility soils. These types of seed grow well even in low temperatures where others can’t grow.

Although they’re a lot of fun on sunny days, sprinklers are more effective at growing grass seed on overcast or cooler days

Don’t stop watering grass seed once you start

Growing grass from seed is a process that takes a few weeks. Grass seed can live for a very long time as they only germinate when in contact with water.

On the other hand, you should keep on watering grass seed once you start. Refraining from proper watering after initial seeding might kill off the seed completely.

Typical grass seed watering mistakes

While not all seed and soils are the same, there are a few watering mistakes that are independent of such variables. The way you water the seed is as important as the grass seed quality.

Uneven watering

Uneven watering is the main cause of grass seed only growing in certain areas of your lawn. Patchy lawn growth might also be caused by uneven seeding. But given the soil has been seeded evenly, grass should grow evenly.

You can prevent uneven watering by having a clear plan on where to sprinkle to cover the entire area of the seeding. If you’re using water sprinklers make sure to space them out correctly so they cover the entire area of the seeding evenly.

Uneven watering is also an issue for lawns on a slope. Some sloping lawns might require a bit more watering at the top of the slope. However, most types of grass seed grow similarly on flat ground as on slopes.

Uneven watering can be an issue for homeowners with lawns that slope


Over-watering is a common problem for those new to grass seed. It can be intentional or unintentional – perhaps you’ve simply forgotten to turn off the water sprinklers.

Timers have been installed on water sprinklers to avoid adding too much water to the lawn. A single day of overwatering the soil can kill grass seed. This is why it’s crucial to water the soil twice per day to maintain high moisture levels but to prevent puddling water at the same time.


Reducing the watering schedule can diminish growth or kill off grass seed completely. Under-watering grass seed are one of the common watering mistakes to avoid.

The highest probability of under-watering grass seed is during the summer. High heat evaporates water from the soil faster and this is when you might need to water grass seed more than during the fall.


Should I water grass seed every day?

Yes, you should water grass seed every day. A morning and evening grass seed watering plan is required for grass to grow thick and healthy. You should continue watering grass seed twice per day for up to a few weeks. Grass needs to be watered once per day once it reaches a few inches in height.

Can grass seed grow only with rain?

Grass can grow only in the rain. It might take longer for grass seed to grow without watering but they can eventually sprout if there’s sufficient rain.

The problem with not watering grass seed is that it eventually dies if it isn’t watered within days or weeks, depending on the species. Only relying on rain can also overwater grass seed. Heavy rain can lead to soil erosion, essentially keeping grass seed from sprouting.

Can you water grass seed in the sun?

Watering grass seed in the sun isn’t recommended – the sun heats the soil, leading to quick water evaporation. This doesn’t allow the seed to be watered completely. Furthermore, watering grass seed in the afternoon sun also leads to higher water waste.

Are timer sprinklers necessary for grass seed watering?

Sprinklers with timers aren’t mandatory for watering grass seed. They are only useful if you aren’t sure about the time it takes to water the soil properly each day. Some of these sprinklers can also be automated so they start watering grass seed on its own.

Are rectangular sprinklers better than spot sprinklers for grass seed growth?

Rectangular sprinklers are recommended for most lawns and help to gently water large and small spaces. Spot sprinklers are only recommended on small surfaces where you might be dealing with re-seeding or lawn repair.

Is watering grass seed at night better?

Watering grass seed at night is not better than watering grass seed in the morning. While water evaporates slowly during the night it’s still best to water grass seed in the morning. Doing it in the morning allows the soil to be cooler for most of the day.

Can I over-water my grass seed?

Yes, you can water grass seed too much. If the soil is puddling, grass seed might not sprout. The perfect soil is moist but never too watery.

Over-watering grass seed can also occur on rainy days when the soil should not be watered at all.

Can I skip a day of watering grass seed?

While you can skip a day of watering grass seed, this is not recommended. Some types of grass seed need constant humidity until it reaches grass height of 2-3 inches. It’s at this stage that you can start skipping watering days.

How often should I water the over-seeded lawn?

You need to water over-seeded lawns twice per day. While grass seed can be seeded next to existing grass you still need to ensure the seed gets constant moisture for proper growth.

Is it best to plant grass seed before or after the rain?

It’s best to water grass seed yourself for the best-looking lawn. If you plan to use rain as a growing nutrient you need to plan to seed accordingly.

The weather forecast can help you with seeding before a light rain. It’s not recommended to plant grass seed before heavy rain due to over-watering risks.

Is heavy rain bad for grass seed?

Fresh grass seed tend to be washed away by heavy rain. They need to be present at the surface of the soil as grass seed need sufficient light to germinate.

If they get washed away from the surface level of the soil, grass seed will not sprout even after a rainy day.