Can you lay sod over existing grass? What you need to know

There’s little that gives a homeowner more pride than having a pristine and well-manicured lawn. Thick, luscious grass certainly adds to your home’s curb appeal, and it definitely enhances your time outdoors with the family. When your grass starts to die, thin out, or turn yellow in certain spots around your lawn, it can understandably be a major disappointment. There are a few ways to address an unhealthy lawn, and laying sections of sod may be a good option for you. However, the process of laying sod can be a vigorous one, so people often wonder, do you really have to pull up those old patches of grass, or could you take a shortcut?

good lawn maintenance
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Can you lay sod over existing grass?

In order for sod to flourish, it needs to establish a root system, and it needs proper nutrients. The best way to get what it needs is for the sod to be laid flush against the soil. This allows the roots to be well established and nutrients to be soaked up through them. Is it so bad, though, to lay sod over your grass? The answer is yes, and here’s why.

The sod will struggle to take root

If sod is laid over existing grass, the roots will have to work hard to get to the soil, and they may be unsuccessful. Then, you’ll see your brand new sod start to yellow and die within just a few weeks. You’ll eventually have to not only replace your new sod, but you’ll also have to pull up the old grass, which will be a slimy, decomposing nightmare underneath.

Old weeds may resurface

When you lay sod over grass, the grass will eventually die and decompose, but weeds are extremely resilient. They will likely survive being covered, and they’ll pop up throughout your brand new sod. If you skip the process of tearing up the existing grass and weeds, you’ll end up needing to eventually pull up weeds after the sod is laid and possibly damage your expensive sod.

Your new sod won’t look as good

Laying new sod over existing grass, particularly if you’re only laying sod in certain areas, doesn’t look as great as properly laid sod. If you lay your sod over grass, even if it survives, it will have a greater height than the rest of your lawn and will result in an uneven and choppy appearance.

lawn landscape with tree and river

How to lay sod

Now that you’re well aware of the problems with laying sod over existing grass let’s talk about how to lay sod properly. Taking these steps will help your new sod flourish, and you’ll be sure to revive the pristine appearance of your lawn.

Remove the existing grass

To remove old grass, you may be able to use a rototiller and a rake if the old grass is thin enough. Till through the section you’ll replace and rake up any debris left behind from grass and its roots. If the old grass is thicker or you’re replacing a large section of lawn, you may want to rent a sod cutter. With this tool, you’ll pull the old grass up in strips, making it easier to manage the large volume of debris. Also, remove about an inch of the old soil so that your new sod is level with the rest of the lawn.

Prep your soil

Till the remaining soil to loosen it up and break up the solid chunks. Loose soil will make it easier for the sod’s roots to become established. Rake the soil as well and make the surface even so that your sod will appear flat with no uneven spots. Sprinkle a thin layer of topsoil onto the soil for some added nutrients. Lastly, water the soil lightly to dampen it before laying your sod.

Lay down your sod

Start flush against the edge of your existing grass and roll out your sod onto the prepared soil in sections. If you have a sloping lawn, you’ll want to lay the sod horizontally on the slope for better water retention. Ensure the strip of sod has full contact with the soil and then lay the next section flush against the first one with no gaps between the strips. Continue until you’ve covered the entire section of soil, and use a sharp tool to trim any remaining sod so that you have no overlapping sections.

After you’ve laid the sod

Water the newly laid sod a couple of times a day for two to six weeks (or until the sod takes root). Try to avoid stepping on or frequently using your yard for up to four weeks after laying the sod. This will protect the newly forming roots and allow them to take hold of the soil adequately.

Having a beautiful lawn is certainly the dream, and it’s actually an attainable one. Even if your lawn is looking drab or discolored, you can simply replace it with new sod by putting in a bit of time and effort. With laying sod, it’s always best to do it right the first time and avoid cutting corners. While laying sod over your existing dead or discolored grass may seem like an innocent shortcut, it’s actually one that will cost you more time, energy, and money in the long run.

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