Overseeding Lawn: How To Plant Grass Seed On Existing Lawn

​The grass on your lawn can affect the overall look and curb appeal to your home.

The weather keeps changing and you can only expect the grass on your lawn to eventually lose its plush and green look.

When this happens, it may be time to grow new grass. However, it’s one thing to start with a bare lawn, and it’s another to plant more seeds on an existing lawn.

If you want to know how overseeding a lawn will help it look green and plush, then this post will let you know what you need and when to overseed your lawn.

Related post: Best Time to Aerate and Overseed Your Lawn

It’s just normal that your grass won’t remain green and healthy-looking for a long time.

In fact, it might only take a few weeks or months before the deep green grass that you have change into something lighter and even thin.

Maintenance is important and planting grass seeds on your existing lawn is the way to go.

The only way to make sure that you keep your lawn lush and green is by overseeding. What does overseeding mean? It’s simply how to plant grass seed on an existing lawn.

Planting new grass seed on the existing lawn is a process that can keep your lawn look healthy and greener than ever.

Before we get into it, we wanted to share our top recommendations of grass seeds that we and our landscapers like to use. Check them out and let us know what you think.

Related post: Seasonal Lawn Care Guide and Tips

What To Do Before Overseeding Lawn

There are a few things to remember before you overseed your lawn. There are different types of grass seeds so you need to make sure that what you’ll use is the same as what’s already on your lawn.

Related post: How Long Does It Take for the Various Types of Grass to Grow?

You can still use your leftover seeds, but know that the success rate of its growth may be less than fresh seeds.

Another thing that you need to do is to assess the reason why your lawn is looking less healthy. You need to check on your lawn’s color and quality of grass.

Check if there are brown spots caused by poor sunlight, fungal problems, and poor soil condition.

These problems need to be addressed first before you start with overseeding. What you do not want is for any of these to hinder the growth of new and healthy grass.

As much as possible, what you’d want is to make sure that the new grass remains healthy for a long time.

How to Plant Grass Seed on Existing Lawn?

So the question really is this: Can you plant grass seeds on an existing lawn?

Simple answer is yes. Through overseeding, you can do spread grass seeds on top of your existing lawn.

It’s not really recommended to plant new grass seed on an existing lawn, however, if the majority of your existing lawn is dead.

Or what I mean is if there are many dead spots on your lawn. You should only plant fresh grass seeds on an existing lawn if it’s still salvageable.

This is why it’s important for you to first assess the situation that your lawn is in.

When is the Best Time to Overseed Lawns?

Your lawn will require maintenance year-round, but it doesn’t really mean that you can overseed any time of the year.

Generally, what’s really recommended is to start this process during the early fall or early spring. However, this will also depend on the type of grass that you have.

It’s best to start the overseeding in early fall if you have cool-season grass like Bentgrass, fine fescue, Kentucky Bluegrass, and Perennial Ryegrass.

On the other hand, you can start overseeding warm-season grasses like Bermuda, Centipede, and Zoysia grass during early Spring.

You should also know that most types of grasses grow best in temperatures between 50 to 70 degrees Fahrenheit.

Know that exposing the seeds to sunlight is also very important as the warmth from the sunlight can encourage germination.

The night time is when the grass could prevent having fungal or any type of diseases.

How To Plant Grass Seed On Existing Lawn

If you feel confident that the soil is all good and your lawn or yard no longer faces any problems that could affect the growth of new grass, then you can already start with overseeding.

It’s generally easy to do this, but here is the step-by-step process on how to plant grass seed on existing lawn.

Prepare your lawn before planting Grass seeds

The preparation process for your lawn consists of a few things. First is that you need to make sure that the existing grass is not taller than two inches.

You can mow your lawn with an electric mower, but if you don’t have a big lawn, you can choose to do this manually.

Related post: Best Reel Mowers to Mow Your Lawn Naturally

After mowing, make sure that you remove the clippings. You can start watering your lawn deeply as it’s best that the soil is soggy before you overseed.

Once your soil is moist, you can start with raking. This is also important as the grass seeds that you will grow must be in contact with the soil. This is also why the existing grass shouldn’t be too long.

Soil aeration is also something you should do. You can use aeration tools for this like plug or spike aerators.

The aeration tool you use should be able to remove soil plugs that are about two to three inches deep, .5 to .75 inches in diameter, and about two to three inches apart.

Doing such things can make sure that the soil is ready and can accommodate enough water. This could also help ensure that your grass seeds will get enough air and nutrients.

Fertilize the soil Underneath Your Lawn

Fertilizing your soil could help ensure that your grass germinates and grows healthily. You can use a starter fertilizer that is high in phosphorous.

However, the kind of fertilizer that you should use will really depend on the condition of your soil.

You can also use a slow-release nitrogen fertilizer. You can put the fertilizer before or after you lay your seeds.

What’s important is that it is mixed well with your soil. You can use the back of a leaf rake to do this. Just make sure that you only rake lightly.

You can also add a thin layer of compost over your entire lawn. Make sure that you don’t overdo this as it could affect the success of germinating your seeds. A very thin layer should already help your seeds and grass grow.

To make sure that your compost is spread evenly, you can use a thatch rake. Check if some of the compost you used is completely flat on the soil.

Avoid leaving some on top of the existing grass. Keep in mind that it’s always best to follow the manufacturer’s directions when it comes to using composts and fertilizers.

Spread and plant your Grass seeds

Once you’re done with the previous steps, your lawn is already prepared to welcome your seeds. You can use a rotary spreader when doing this.

You can also this manually with just your hand. The general rule is to follow the instructions from the manufacturer when it comes to planting your seeds.

Make sure that you have your seeds spread evenly and have enough on spaces where you should focus.

After spreading the seeds, have your lawn lightly raked. This will help the seeds settle on the soil. It could also help make sure that all your seeds are touching the soil.

Water Newly planted grass seeds

Make sure that you immediately water your lawn after overseeding. Keep on watering your lawn three to four times a day until you notice that the seeds have already germinated.

Germination can happen in the first several weeks after you overseed.

Another thing that you should do is to make sure that you soak the soil well. This is as long as you haven’t seen your seeds starting to sprout.

It’s usually 10 to 14 days before this happens, and once it does, you should only soak the soil one inch deep.

Related post: How Long Does It Take For Grass Seed To Grow After Overseeding?

The technique is that you should never allow the seeds to dry out. It should only be after the germination process that you decide to water less frequently. Keep in mind that too much water can kill the seedlings.

If you are looking for a new oscillating sprinkler, we highly suggest you look at this oscillating sprinkler. It’s super easy to connect to your hose and it has a built-in self-timer. It’s one of the best sprinklers out there now.

Come up with a maintenance routine For your Lawn

Your lawn maintenance includes watering, mowing, and fertilizing only when it’s needed. When the grass is fully grown, watering should only be done once a day.

Mowing and weed control is also important. As soon as you see weeds growing out, make sure you have them removed immediately.

When it comes to fertilizing, the best time to do overseed your lawn is every spring or when the temperature is around 55 degrees Fahrenheit.

Six weeks after the germination process, you can use quick-release nitrogen fertilizer again.

Just make sure that you avoid overfertilizing as this could also kill your grass. Nitrogen fertilizer, in particular, can burn the grass and dry them out quickly.

Can You Overseed Over Dead Grass?

A direct answer to this is simply yes, you Can seed over dead grass. However, I don’t recommend this at all as it will simply make your lawn look like a mess and even abandoned.

If your lawn is only composed of dead grass, then it’s best that you remove the dead grass completely.

If your lawn only has a few spots with dead grass, just remove those spots and make sure that you put enough seed on those areas.

Generally, total lawn renovation is best if your lawn only has dead grass. This is to make sure that your lawn ends up looking good once the seeds have already grown.

Related post: Will Watering Dead Grass Bring My Lawn Back Life?

Can You Plant Grass Seeds Over Weeds?

The short answer to this question is yes, you may reseed your lawn with weeds. However, I wouldn’t really recommend this. Even most gardeners wouldn’t recommend this too. The problem with planting grass seeds over weeds is that it’s simply frustrating.

You can do this, but it’s almost guaranteed the results will never be what you want for your lawn.

Weeds are generally hard to get rid of and it could be very annoying. The best thing to do is to start fresh and bare.

If you are looking for a very good weed killer and crabgrass killer, we highly suggest this crabgrass and weed killer. It simply works – no other explanation or pros/cons are needed.

Will Grass Seeds Grow if You Just Throw Them on The Ground?

It’s simply not ideal to just throw grass seeds on your lawn or ground. It’s important for the seeds to touch the ground in order to germinate.

It’s true that there’s still a possibility that the seeds will sprout if you just throw them away, but this won’t guarantee a hundred percent germination.

It’s ideal to rake the ground after scattering the seeds on your lawn. This will make sure that all the seeds you planted will sprout and germinate.

It could also make sure that they get the moist they need that could help them sprout nicely.

Should You Rototill Your Lawn Before Overseeding?

While there are some gardeners who do this, I’d say this isn’t really necessary. Using a rake or a lawnmower is just fine before you overseed.

In fact, it’s only recommended to mow your lawn if the existing grass is above 2 inches high.

Other than that, raking is fine. Rototilling your lawn may only be required if it has more dead spots.

This is going to be more useful and efficient if you’re renovating your lawn rather than just overseeding it.

Do I Need to Overseed Lawn Every Year?

The truth is that you can do this as much as you prefer. However, what’s really recommended is to only overseed or reseed every three to six years.

That’s the general rule. However, this will really depend on the health of the grass on your lawn.

If you see your lawn unhealthy in just a year or two, then you can already overseed then and there.

However, if you see that your lawn is still looking good after three to four years, then you don’t have to reseed or overseed yearly.

Can You Plant Too Much Grass Seeds?

It’s a common misconception that when it comes to planting seeds in general, the more the merrier is applicable. This is really not the case, especially when you are overseeding or reseeding your lawn.

What you really should know is that using too many seeds won’t really make your lawn look lush and healthier.

In fact, too many grass seeds trying to grow at the same time can make germination a struggle.

You need to keep in mind that all types of plants, including grass, need space and enough nutrients to germinate and grow healthily.

When there’s just too many of them, healthy growth may not be possible.

A Few Things to Keep in Mind Before You Overseed Lawn

What’s really important is that you start overseeding when it’s best to do so. What could also help is that you really maintain your lawn.

It could require much time and effort to do so but having a green and lush lawn should be enough motivation to keep at it.

Generally, only reseed or overseed if your lawn isn’t looking lively anymore. If the majority of your lawn appears dead, then start fresh.

If you only have a few spots that don’t look right, then just reseed. Make sure that you don’t use too many seeds and that you keep your seeds well-hydrated and moist. If you have extra seeds, find out more about whether you can keep grass seeds for the next season.

Now, these are the steps that you can follow to effectively overseed your lawn.

Again, make sure you first take care of the problems that your lawn has to make sure that healthy grass growth is possible.

With all these tips, you’re now ready to bring back the life that your lawn used to have. Happy seeding!