Having clay soil leaves a bald and sad-looking patch in your yard. Learning how to improve clay soil for lawns will help you give your space a chance to green up. The best soil for grass should contain an equal distribution of soil, organic matter, air, and water.
The clay soil particles are too small that clump up when dry and become mushy when wet. Since it is too compact, beneficial life forms like earthworms and bacteria in the soil can’t access oxygen, water, and nutrients.
The best approach to break up clay soil and allow life to flourish in it is through the combination of soil conditioners, organic matter, and core and liquid aeration.
How To Know If You Have Clay Soil?
Not all mushy and bald spots in your lawn are due to clay soil. Some are probably due to drainage problems and low terrain. Some homeowners who just moved into their new home may also find it hard to identify if they are dealing with clay soil or if the lawn needs soil amendments.
Here are some telltale signs that you have clay soil in your yard:
- Grass no longer responds to fertilizers: Due to the compact nature of clay soil, the nutrients from the fertilizers can’t squeeze their way to the grassroots. The buildup of fertilizer on top of the clay soil can also burn the grass chemically.
- Puddles of water on the lawn: Clay soil has poor drainage, which causes the water to build up and drown the grassroots.
- Splitting parts in the soil: When the lawn is dry, you will often see the soil breaking up and creating unusual cracks between hard clumps of soil.
How to do a soil test at home?
If you are still unsure if you have clay soil plainly by looks, you can do a simple clay soil test. Here’s how:
- Mason jar
- Dish soap
- Soil samples
- In a basin, place the soil that you want to check. Remove any debris and rocks to keep the accuracy of the test.
- Put the soil samples in the mason jar and leave half of it empty.
- Put one teaspoonful of dish soap above the soil samples.
- Fill the jar will water and cover it with the lid.
- Shake the mixture well until all its contents are floating in soapy water.
- Let the particles settle for 24 hours.
- After 24 hours, you will notice a distinct separation between soil particles. The bottom layer is sand because sand has a bigger particle size. The second layer is silt, while the topmost layer is clay.
- To know the type of soil you have to measure each layer with a ruler and compare the ratio. If the clay is around 20 millimeters or more than sand. Then, you can tell that you have clay soil.
Breaking Up The Mud: Mechanical Steps in Improving Clay Soil
The no-till approach can take a lot of time before the clay soil is suitable for grass. Most professional gardeners recommend the combination of adding soil amendments and mechanical methods in navigating how to improve clay soil for lawns.
These methods include:
Core aeration is the process of turning compacted and hard soil to break clumps, remove rocks, and allow the soil to breathe. It is a process that uses mechanical equipment such as a soil-aerator, rototiller, or a tow-behind tiller to process 6 to 10 inches of clay soil.
Deep Core Aeration
Deep core aeration is an optional method where you till the soil deeper by reaching 10 to 12 inches deep. It allows you to reach areas in the clay soil that tow-behind tillers can no longer dig.
In this method, you will use a drill with a 24-inch auger bit to make deeper holes.
Topdressing is the practice of applying compost or sand on top of the soil. Topdressing clay soil with compost helps only requires ¼ inch of compost or sand on top of grass or tilled soil to improve the soil composition and add more nutrients.
Nourishing The Soil With Nutrients From Organic Sources
Before core aeration, gardeners perform liquid aeration first. Liquid aeration is the method of using a wetting agent that softens up the soil chemically. It makes core aeration easier and digs deeper.
A soil conditioner like Simple Lawn Solutions Liquid Soil Loosener is a good option for managing heavy clay soil.
Gypsum is a soil conditioner made of calcium and sulfur. It naturally aerates the soil by working with clay molecules, breaking clumps, and allowing air and water deep into the soil. It is also a good source of calcium without changing the soil pH level.
Compost is a nutrient-rich soil amendment that is crucial in preparing your lawns. It can hold moisture and contains humus, which is the broken-down form of organic matter.
The humus in compost helps feed life forms in the soil like beneficial bacteria and earthworms. It is also rich in nitrogen and potassium, both essential in grass growth.
Aside from improving the soil composition of your lawn, compost also helps encourage earthworms. The presence of earthworms helps naturally till the soil, and they leave wastes called worm castings which helps nourish grass development.
Soil Allies: Earthworms and Plants That Can Grow in Clay Soil
Working on clay soil is a laborious project, but there are some hacks that you can use in naturally tilling the soil. Aside from mechanical equipment and lawn solutions, you can also count on some plants and earthworms in tilling and aerating the soil.
Check out how these two allies can help speed up your lawn improvement:
Earthworms help soften the soil by tunneling around, feeding on organic matters, and leaving nutrient-dense worm castings. Worm castings are broken down organic matter that is good for soil microbiome and grassroots.
Planting Soil Tillers: Green Beans And Radish
Planting daikon radish on clay soil is one of the practices done by farmers to allow the radish crops to use their invasive roots to soften compact soil. Radish produces taproots that will naturally break clumps of clay soil and dig deep.
Green beans are soil nitrogen-fixers that can turn heavy clay into a conducive environment for growing grass. It is an ideal hack to save on spending on nitrogen fertilizers while growing your food.
Step-By-Step: How To Improve Clay Soil For Lawns?
Combine both mechanical methods and add soil conditioners through this step-by-step process in improving clay soil.
Step #1: Liquid Aeration
Liquid aerator solution contains heavy-powered soap that helps water get through the hard soil. Spray the recommended liquid aerator based on the space that you have. It’s best if you can water the area while waiting for the results. Leave it for about one to two days to allow the solution to work on the hard soil.
To see the difference and gauge the hardness of the soil, we recommend using a broadfork before and after applying the soil conditioner. The benefit of using liquid aeration before core aeration is it allows the tines of the tiler or aerator to go deeper into the soil.
Step #2: Core Aeration
Since the soil is already treated with liquid aeration solution, the tines of the tow-behind tiller can now go deeper into the soil. You will notice that there will be less resistance in clay soil, making it faster for you to increase the depth on every pass.
One good practice in core aerating clay soil is to avoid forcing the tines to dig deeper. Start slowly and increase the depth as soon as you nice that there is less resistance between the soil and the tines. Pushing the limit of your tiller will damage its tines.
Step #3 Deep Core Aeration
Some gardeners do the extra mile by drilling deeper holes after core aerating the soil. They use a 3×24-inch auger bit attached to a drill and create holes around the treated area. The auger bit helps dig up to 12 inches deep in the soil.
The benefit of deep core aeration is it gives grass more opportunity to grow deep roots and move freely underground. However, it is an optional step you may skip if you lack the tools and time to do it.
Step #4 Mulching
After breaking down the clumps of soil in your lawn, you can now let air water, and organic matters get into the holes and spaces in the soil. You can mulch your treated lawn with compost, aged animal manure, or dried sunflower stalks.
Compost and animal manure are common mulch options in gardening. However, dried sunflower stalks is an underrated option that farmers use to mulch garden bed and lawns.
Sunflower stalks contain a powerhouse of nutrients, such as potassium, phosphorus, calcium, and magnesium, which are beneficial for the soil microbiome and grass. Aside from sunflower stalks, you can also add gypsum at this stage to improve soil compaction and allow more nutrients and water to penetrate the soil.
Leave or rake the mulch with the topsoil and wait for several days to encourage earthworms in the area. The organic matter will break down and work its way into the soil, creating a balance of clay, silt, sand, and organic matter.
Step #5 Topdressing
For the last step, you should topdress the soil with either compost or manure or a combination of both. Landscape artists recommend using 50% compost and 50% manure in topdressing the lawn for better results.
The earthworms in the soil and the mechanical process you did in the first steps will add up to the aeration of the clay soil. The top dress will amplify the texture of the soil, make it softer, and add more nutrients to the soil in preparation for seeding.
Pro Tip: When you plan to seed with cool-season grass, you must apply a light seeding and starter fertilizer after topdressing the lawn. Unlike warm-season grasses, cool-season grasses do not spread horizontally underground, so you have to start them early.
Balancing The Good Qualities of Clay Soil and Loam Soil
Most gardeners say that gardening using clay soil will keep you working. However, despite its troublesome compaction, clay soil also have some benefits that other types of soil do not possess, such as:
- Moisture retention: Loamy clay soil can hold more moisture and keep the temperature low for the roots. It is a quality that can help reduce the impact of drought and temperature stress on the grass.
- Nutrient-dense: Due to the dense consistency of clay soil, it holds a lot of nutrients that do not easily leach into the ground.
- Amplifies the effect of slow-release fertilizers: You will also get the most out of slow-release fertilizers because the clay qualities of the soil will help retain the nutrients until they are absorbed by the grassroots.
Through the help of aeration, compost, and lawn maintenance, loamy-clay soil can still be a workable option in growing lawn grass.
Till or No-till?: Which Is Better For You?
Tilling lawns has opened a lot of debates about whether it’s necessary or not. Many advocates of no-tilling practices aim to showcase that it is possible. However, it takes a lot of time before the soil reaches the ideal condition to grow grass.
If you have the patience and are incapable of doing laborious tasks, like core aeration, you can go with the no-till approach. Otherwise, you can improve the clay soil in your lawn in the five steps mentioned above.
What Are The Ideal Grass Varieties For Loamy-Clay Soil?
The grass you should grow in loamy-clay soil should tolerate poor drainage and temperature changes. These include:
- Cool-season grass: Tall fescue, perennial ryegrass
- Warm-season grass: Bermudagrass, buffalograss, zoysia
Learning how to improve clay soil for lawns can make you feel overwhelmed with the amount of work that you have to do. However, every gardening challenge makes skillful gardeners. If you lack some equipment, you can borrow some from your friends or rent one in the nearest hardware store in your area.
In landscaping clay soil, you should also consider that there are different ways of working with clay soil. The methods we mentioned here are one of the many patterns that gardeners use. Some consider the series: core aerate, liquid Aerate, top dress, seeding, and fertilizer and still land on the same results.
The pattern that you must follow will depend on the kind of soil you have and the reaction of the clay soil to the methods you’re using.
We hope that this post helped you improve the clay soil in your lawn. We long to help you amaze other gardeners on how you managed to make clay soil a viable growing medium for a lush lawn. If your friends ask what’s your secret, please don’t forget to share this post with them.
Also, please leave a comment on how you were able to turn your dry clay soil into a lush green lawn.