How to Improve Clay Soil for Lawns

Clay has the potential to be one of the best soil choices for grass growth because the individual particles are very small and hold water and nutrients needed for lawn growth much more effectively. However, it is also a very dense and compacted soil, which results in the possibility that less air, water, and nutrients will flow to the roots. Today we will teach you how to improve clay soil for lawns.

How to improve clay soil for lawns.

You can improve clay soil for lawns. Clay soil is compacted and needs water, air, and nutrients to survive. If you systematically test and aerate your clay soil and incorporate organic matter via top-dressing and tilling, you will improve your clay soil year-round. 

It is Possible to Improve Clay Soil for Lawns

Many homeowners think that clay soil is a death sentence when it comes to growing grass.

And that can be true in certain situations. If you do not take the time to improve the clay soil in your lawn, it can result in stunted roots, weakened grass, and even greater numbers of insects and weeds.

However, there are a few simple steps you can take to improve the existing soil. Read on to learn how you can improve your clay soil and grow a beautiful and lush lawn.

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Test Soil Density to Improve Clay Soil

Determining the soil quality of your yard is an important first step.

Testing your soil will show you exactly what you need to add in order to improve it for future lawn growth and health.

The last thing you want to do is try to guess what your lawn needs and make the wrong improvements which could possibly make the soil worse.

All you need to get started is a soil testing kit to test the nutrients in the soil and a simple hand test to examine the soil’s density. 

The store-bought test will measure the different nutrients, such as potassium, phosphorus, and nitrogen, in the soil.

To test your clay soil’s density and type, simply scoop up between a half cup and a cup of your clay soil and soak it with a few drops of water. Create a large ball of the soil with your hands: 

  • If it breaks at one inch – you have silt or loam
  • If it breaks at two inches – you have clay loam
  • If it breaks at more than two inches – you have heavy clay ( it is good to test this type every three to four years) 

Once you determine the soil’s nutrients and the type of clay, you can figure out how to improve the clay soil for your lawn.

First, you will need to properly aerate your lawn. Then, use the soil test results to choose the type of organic matter and how much will work best to top dress your lawn and further improve your clay soil.

Aerate to Break Up the Soil

Clay soil is compacted and has very little air space, so aerating your lawn is a great way to improve the clay soil.

Clay is composed of microscopic particles that are stuck tightly together, which inhibits oxygen, water, and nutrients from flowing freely throughout. 

  • Aerating compacted clay soil will help the air, water, and other nutrients you tested reach your plant’s roots and foster valuable soil-building microbes.
  • Aerating needs to be done once a year, preferably in the spring or fall (this timing depends on the type of grass on the lawn), to maintain your lawn’s wellbeing year-round. 

For an easy DIY method to aerate your lawn, you can simply poke small holes throughout the lawn with a fork by starting at one side and poking the holes every four to five inches until the entire lawn is done. This can be time-consuming and tedious but works well for small areas.

If you have a large yard you may want to purchase spike aerators or pull-behind aerator to break up your compacted soil faster and easier.  

Top-Dress with Organic Matter

Once your lawn is aerated, you should top-dress the clay soil.

You should do this twice a year with compost or organic matter.

Incorporating organic matter is probably one of the most important steps to improving the condition of your clay soil for your lawn. 

To apply topsoil to your lawn you will:

  • Apply a thin layer ( ¼ to ½ of an inch) of the organic matter over your lawn. Apply more to level out areas where you have holes or dips.
  • Use a rake to make sure the organic matter is worked down enough, so it touches the soil. The organic matter needs to be worked down to where the roots grow. If it does not touch the soil, it will not help improve the clay matter.
  • In clay, in particular, organic matter will entice earthworms to tunnel through and help oxygen flow.

When choosing what type of compost or organic matter to use, nearly anything will work. Some popular choices include manure, compost and gypsum.

The correct organic matter will decompose nicely and gradually improve your clay yard.   

However, do not choose sand to mix into your clay soil because it may end up making your clay too hard.

Beware of Thatch

It is important to note that the nature of clay may cause lawn debris to accumulate on the top of the soil and develop into what is called thatch.

Too much thatch will inhibit your lawn from getting the important nutrients it needs. You can test whether your clay soil has developed too much thatch simply by walking on it. 

If you walk across your lawn and it feels spongy, there may be too much thatch. This is why aerating is so important. Both heavy clay soil and thatch will prevent air, water, and important nutrients from giving your lawn the nutrition it needs.

If you believe that your lawn has become covered in thatch you will need to dethatch before top dressing.

How to Improve Clay Soil Fast

To be completely honest with you, the process of aerating, dethatching and topdressing your soil will not result in overnight improvements to your lawn.

Depending on your soil conditions it can take a long time for the nutrients in the organic matter to travel down through the clay soil particles to reach the roots of the plant and actually impact the condition of your soil.

It’s just a slow process when you’re trying to change the composition and structure of the soil in an existing lawn.

The good news is that there is a product that can speed up the process.

A liquid lawn aerator can be applied to your lawn twice a year which will help to loosen and condition clay soil even faster.

We suggest that if you have extremely compacted clay soil that you continue to do manual aeration and supplement with the liquid aerator to break up your soil so that the water can soak in and carry the nutrients to the roots. This is a great solution for an established lawn that just needs a little more help.

Liquid Soil Loosener- Soil Conditioner-Use alone or when Aerating with Mechanical Aerator or Core Aeration- Simple Lawn Solutions- Any Grass Type-Great for Compact Soils, Standing water, Poor Drainage
  • Liquid Soil Loosener: Can be used Alone or with Mechanical or Core Aeration, Aerating and Aerate Tools. Liquid Soil Loosener Conditions Compact Soil. Helps the Downward Movement of Water Allowing Vertical Drainage and Increased Water Infiltration.

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Once you have gotten into the rotation of testing, aerating, top-dressing, and dethatching, you will start to notice vast improvements in your lawn over the course of about 4 to 6 weeks. As the nutrient levels and compaction of your soil is improved your lawn will begin to look it’s best.