How to improve clay soil for lawns

Does clay soil make your lawn look sparse and lifeless?

Don’t worry! There’re many easy-but-efficient ways to amend and correct it for thick, green lawn growth as you’re dreaming of. Here is some little know-how that lots of experts prefer to apply.

How to know if you have clay?

There are some physical tests to let you identify clay soil lawns.

While digging, you’ll feel it like a sticky mess if the soil is too wet.

Conversely, when it’s too dry, it feels like you are digging into concrete.

If you’re still not sure if you have clay, do a simple test, called the ribbon test.


Rub a moistened bit of soil between your pointer and thumb. The longer the ribbon, the heavier the clay soil that you have. If it’s over 2 inches, the soil must be clayey and you have to think about how to incorporate more organic matter into it.

How to improve clay soil for lawns

Things you will need

  • Tiller
  • Soil test kit (find at home improvement stores or garden centers)
  • Aerators
  • Top-dress
  • Grass seeds
  • Water


1. Test the soil

By measuring the amount of potassium, phosphorus, and nitrogen, this very first step helps to determine the nutrients, pH, and fertility that are lacking in the clay soil.

If you can’t do this at home, another way to get the results of the soil testing is to bring a soil sample to your local cooperative extension office. This is where they will provide a list of recommended soil testing labs or analyze it for you.

test soil

2. Measure the lawn’s area

To know precisely the lawn’s clay soil area that needs amending, multiplying the length and width of the lawn together. After getting the garden’s square footage, subtract the areas that needn’t correct. Here, you’ve got the total clay soil area.

Don’t skip this step because it will be very useful for you to calculate the needed amount of soil amendments, especially fertilizer.

3. Aerate the soil

The drier the clay soil, the more restricting drainage it will be, which limits the amount of oxygen to reach the grass’s root system.

To let oxygen and water freely move through it, you have to regularly aerate the soil, remove plugs of dirt from the lawn and leave behind countless small holes in the ground. By doing so, it allows the grass root to spread as well.


Aeration requires proper season and times.

It should be carried out during warm seasons (such as late spring and early summer) or cool seasons (such as autumn and early spring). The best time to aerate the soil is during the growing season or after the ground thaws (when soil is moderately moist)

Twice a year is a good frequency.

If your lawn is small, a pair of aerating spiked boots is the most convenient. Conversely, bigger aerators that can be rent from equipment companies or home improvement stores.

4. Spread top-dressing to the soil

Three common ingredients of top-dressing are:

  • Peat
  • Loam
  • Sand

The ratio will change based on the location and type of soil.

For clay soil, the formula is 1 part of peat + 2 parts of loam + 4 parts of sand.

Every 17 cubic feet (or 1 yard) of this mixture is enough for 600 square feet of area.

You should top-dress the lawns in September, after aerating the soil. If you’re rehabilitating a large highly-neglected lawn, it’s better to work with a heavy-duty tiller.

Start with spreading a thinly 1/2-inch layer of the mixture over your lawn and rank it into the surface to make the soil looser, allowing the existing grass to grow into it. For isolated problem spots, use either a heavy garden rake or shovel to break the clay soil up.

Next is a thicker layer to smooth out bumps, holes, and dip.

You can have a truckload delivered if that’s a large lawn or purchase in bags for small lawns.

5. Plant the grass seed

If it’s a lawn overhaul, you can restart with some clay-friendly grass seeds as below:

  • Zoysia
  • Buffalograss
  • Bermuda
  • Tall rescue

plant the grass seed

It would be ideal if the existing grass type on your lawn is one of these. Otherwise, you might need to remove them and start over and patiently wait for several months until it gets established well.

Let your agricultural extension office help you to determine the grass type that your lawn is made of.
When overseeding the grass seed, remember to follow the rate recommended on the bag’s instruction. Use a leaf rake to work all seed down to the soil.

Overseeding doesn’t require straw scattering over the entire lawn but if you’re planting, this extra step is turn out essential.

6. Watering & mowing

Make sure to periodical water the lawn (once/day during the first week) to keep the mixed organic matter and clay reasonably wet.

watering and mowing

If you’re seeding during spring and summer, the growth of the grass will be much faster than during fall and winter.
In terms of mowing, don’t do that until your new grass has at least 3” tall (usually take at least 1 month). During this period of time, keep everything and everyone (consisting of your mower and you) off the newly overhaul lawn.

When it’s suitable for mowing, allow the clippings to fall in the places where they might and take advantage of them as an organic material for your lawn.

Don’t worry, they don’t cause thatch at all!


After the first month of your newly renovated lawn, ensure to water them regularly 1” of water weekly to provide enough moisture to the top 6” of soil.

When mowing, ensure your mower’s blades are sharp to slice young grass cleanly without causing damage to them.
That’s all for this article. Thanks for reading!