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How Much Topsoil Do I Need For Sod?

Growing and maintaining grass can sometimes feel like an impossible undertaking. Have you recently laid down sod but don't know how much topsoil should follow? Do you need to put down topsoil before or after planting sod? Well, we've done some research and have all these answers below! Let's get into it.

Ideally, you want to use 4-6 inches of loosened, nutrient-rich topsoil for your sod. Applying topsoil before/after sod can ensure it develops healthy roots and transitions into a flourishing green lawn.

With that said, if your soil is rich in nutrients, you might only need to till the soil before laying your grass down, rather than apply additional soil.

Again, this can depend greatly on your location and growing conditions, so everyone will be different.

As we begin, we will cover all things sod and teach you how to grow a lush, healthy lawn. Whether this is your first time trying this method of grass growing or you're replanting before the spring season, we're here to offer some guidance. With that said, let's dive right into this post!

Laying grass sods at the backyard, How Much Topsoil Do I Need For Sod?

Do You Have To Apply Topsoil Before Sod?

Although applying topsoil before/after sod can be beneficial, you aren't technically required to do this. Generally, you want to lay down up to six inches of topsoil before planting sod to ensure its roots have a place to grow.

However, if your soil is full of nutrients and is in good health, you might be able to get away with tilling the ground instead of purchasing and spreading fresh dirt.

This can all depend on where you live, what you're growing, and the climate, so don't assume your ground is ready to handle fresh sod with no preparation.

Young man laying grass sod on ground

Even though sod is more established than grass seedlings, that doesn't mean it isn't still sensitive. Grass tends to be temperamental, so you want to ensure everything is perfect before planting.

According to Red Hen Turf Farm, laying down topsoil can also increase a soil's water and nutrient holding capacity, meaning you won't have to fertilize your sod as often.

Furthermore, this increased water holding capacity means you can go longer between watering your sod.

What Does Topsoil Do?

Hand with topsoil

One of the primary purposes for adding topsoil to your existing ground is to replenish its nutrients. Think of this fresh layer as a way to enhance your garden's quality without needing to replace all the soil.

Topsoil typically contains decomposed plant matter (organic matter), which will give your sod and other plants plenty of nutrients to establish a flourishing root system.

You can also use topsoil to replenish erosion areas in a given plot of land. Suppose your new lawn is at the base of a hill or slope.

Laying down topsoil before your sod can help fill the ground and even it out before your grass. Doing this will also help with your land's health, which can be negatively affected by frequent mud/landslides.

As we covered earlier, adding topsoil before sod can increase its water capacity, which is perfect for those wanting to cut back on irrigation/water costs.

Growing grass can be an expensive, water-dependent task, so anytime you can save, that's a win.

Can I Lay Sod Directly On Dirt?

Yes. You can sometimes lay sod directly on dirt without adding additional topsoil.

However, you don't want to do this unless the ground in your yard is soft/mildly compacted, as your grasses' new roots won't be able to develop in heavily compacted soil.

Tilling is another alternative to adding fresh topsoil, but it will require you to do some manual labor.

Experts recommend testing your soil beforehand, so you aren't planting sod over the severely packed ground. The key here is getting the ground soft enough so that roots can make their way through and develop.

Additionally, heavily compacted soil doesn't tend to be packed with nutrients or have good drainage, which is another essential condition your sod will need.

So, if you're on the fence about topsoil, we certainly think it's worth considering for your sod.

What Happens If You Don't Till Before Laying Sod?

If you skip tilling before sod, a few things can happen. As we mentioned, tilling is not usually the first step before laying sod, as topsoil is an easier, less labor-intensive option.

Also, if the dirt in your garden is soft and in good health, there isn't much reason to till it.

According to Pepper's Home And Garden, tilling can cause old weeds to sprout from the ground, affecting your freshly laid sod.

In addition, tilling (if not done correctly) can cause your lawn to grow unevenly.

Not only is that aesthetically unappealing, but it's also can lead to bald spots on your lawn. On top of those potential adverse effects, you also want to consider the price of renting equipment for tilling.

Considering that you'll need to rent/purchase a rototiller, this can set you back between $36-$150, depending on the size of equipment you rent.

On the other hand, buying a rototiller will cost you anywhere from $65-$200, so this isn't a cheap alternative to the topsoil as many think.

What Do You Put On Freshly Laid Sod?

Gardener applying turf rolls in the backyard

Liquid fertilizer is best to put on top of freshly laid sod. Considering how easily liquids will seep into the sod and roots below, fertilizer is the perfect next step in the grass-growing process.

Typically, you'll want to consult a lawn care professional about which fertilizer is best for your sod, as this will vary depending on your climate, grass type, and ground health.

As we said earlier, you can also spread a thin layer of topsoil above your sod if you want to help increase the ground's nutrients further, but this isn't required.

A good fertilizer formula for fresh sod is 10-10-10 or 2-1-1, but this can vary depending on where you're living and the ground's health.

Should You Fertilize New Sod Right Away?

No, it isn't generally the best idea to apply fertilizer immediately after laying down sod. You want your grass to settle into the soil before adding any additional nutrients or formula.

According to Everglades Farm Equipment, you want to give your sod about 30 days before applying a liquid formula straight to your grass.

Applying a concentrated fertilizer to your sod four weeks after you lay it down is best, as this will give your lawn a boost of energy to continue growing and maturing into the summer/fall season.

After that first fertilization, you want to wait until your lawn's growing season to apply more plant food.

Even though fertilizer gives your sod a boost of energy and nutrients, overdoing it can be detrimental to your lawn's overall health.

Sometimes, highly concentrated formulas can burn your grass, causing dead patches if you go overboard.

Is Sod Easy To Grow?

Laying grass sods

In general, it should be pretty easy to grow sod. One of the many reasons people prefer sod over growing grass from seed is that it establishes quickly.

Typically, your sod will develop roots within 2-3 weeks post planting, which is much faster than waiting for each blade to sprout if you try the seed method.

Of course, not all sod will follow the same growing speed or pattern.

Depending on where you live and the conditions around your grass, the establishing process can take slightly longer than 2-3 weeks but won't surpass four weeks in most cases.

As long as you give your newly laid sod enough water and sunlight, you should notice your lawn fills out pretty fast.

Additionally, if you put down topsoil before your sod, that will only speed up this process. Regardless of what you're growing, you're bound to see better results if the soil has more nutrients and water capacity.

Is Sod Easier To Grow Than Seeds?

Grass seeds in the hand

Usually, yes, growing sod is easier than growing seeds for your lawn. With that said, this isn't always true, depending on how well you prepare the soil for fresh sod.

As we covered, skipping topsoil and tilling can mean your sod has to try and establish itself in heavily compacted or poor-quality ground, which can sometimes mean dead patches of grass.

Not only will this mean you've wasted time, but also money.

Purchasing sod is significantly more expensive than seeds, so you want to plant it according to the recommended guidelines.

When it comes to labor intensity, sod is the easiest option for a lawn.

If you decide to grow your grass from seedlings, you will need to spread them, apply topsoil, rake your property, and water the area frequently, which can become tiring over the course of a month or two.

On the other hand, laying down sod is pretty self-explanatory. All you need to do is prep the ground with topsoil or tilling, place your sod squares onto the ground, give everything some water, and watch the grass fill out.

Again, that doesn't always mean sod is easy to manage, but in general, you shouldn't run into too many issues.

To Wrap Things Up

Whether you want to replant your grass or haven't tried growing any yet, knowing how to handle the soil beforehand is essential. From what we found, the ideal amount of topsoil for sod is between four and six inches.

Generally, you want to test your soil before laying down sod and applying topsoil if it's compacted or in poor health. Sod, although easier to grow than seeds, can be temperamental, so try to follow the instructions with the sod type you purchase.

Regardless, give your grass plenty of nutrients, and don't forget to add topsoil beforehand to save on water later!

Made it to the end? Check out these helpful related lawn care posts below!

How To Make Bermuda Grass Dark Green [5 Helpful Tips]

Can I Put Topsoil Over Existing Grass And Reseed?

How Long Can Grass Seed Stay Dormant