When you are laying new sod for your lawn, soil preparation is key to allow the sod to take root and flourish as a healthy lawn. The steps you need to take to prepare your soil for sod:
- Use a sod cutter to remove existing grass and weeds.
- Go over the ground and clear away rocks and debris.
- Till the soil to a depth of 6 inches (15 cm).
- Perform a soil test to determine soil pH.
- Add lime (if necessary) and fertilizer, tilling it into the soil.
- Spread additional topsoil as necessary to level and grade your yard.
- Roll the soil to prevent uneven settling.
This prep work makes laying sod quick and easy, and sets the groundwork for easy sod care. By following these steps, your sod won’t dry out or die. It will take root quickly and become an established yard in a single growing season.
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7 Steps to Prepare Your Lawn for New Sod
The cause of most new sod failures is poor soil preparation. Sod laid over nutrient-deprived or compacted soil struggles to take root. This makes the sod prone to drying out and dying. To prevent your sod from dying, it’s essential to follow the correct process.
Remove Existing Grass
You should never lay sod on top of existing grass or without getting rid of weeds first. The new sod won’t root and the plant material below will turn into a slimy, yellow mess. Not only that, but laying sod on top of existing grass raises the level of your yard by about 1 inch (2.5 cm). This can create drainage problems and lead to flooding. To prevent this:
- Rent a sod cutter from a local hardware store.
- Use the sod cutter to remove existing grass, along with the top 3/4 inch (2 cm) of topsoil.
By cutting out any existing grass, along with the roots and old topsoil, you allow sod to be laid on soil where it can take root.
Get Rid of Rocks and Debris
Once your old yard has been removed, scour the lawn for any stones, pieces of vegetation, or other debris. Grass grows best in soil that is clear or rocks and other obstacles.
- Remove rocks, leftover plant material, plastic, and roots from the yard.
- Cleanup is essential for better sod rooting and to prevent damage to your tiller in future steps.
After cleanup, your yard should be free of any obstructions that could damage rototiller blades or become tangled in them.
Till the Soil
Buy or rent a rototiller to break up the first 6 inches of topsoil. Grass roots typically go down about 6 inches when the grass is fully established. Hard soil prevents this, leading to weak grass with shallow roots. Sod that tries to root in hard earth is prone to death from drought or heat.
- Use a rototiller to till soil down to 6 inches in depth.
- Operate the rototiller in a back-and-forth pattern across your lawn, similar to mowing.
- Work slowly and carefully. Tilling may be slow going in compacted, clay, or rocky soil.
Most soil benefits from tilling before you lay sod. If your lawn has had regular fertilizer applications in the past, has a healthy pH balance, and is not compacted, then in some cases you can lay sod without tilling. However, when in doubt, till.
Perform a Soil Test
At-home soil testing kits are inexpensive and a great way to find out what your lawn needs. Before you lay sod, test it to see if your soil is in the right condition to allow your new grass to grow.
- Use this soil tester to determine your soil pH.
- A pH between 5.8 and 7.2 is ideal for new sod.
- If the pH is lower than 5.8, your soil is too acidic and needs lime.
- If the pH is higher than 7.2, your soil is too base and needs sulfur.
Sod laid on unhealthy soil will struggle to gather nutrients through its root system. Unhealthy soil essentially “locks” nutrients away, meaning any fertilizer you add won’t feed your sod. You’ll want to correct unhealthy soil pH before sod installation.
Apply Soil Amendments and Fertilizer
Now that you know if your soil needs pH correction, it’s time to give the ground what it requires. Apply lime or sulfur to rebalance pH. Additionally, use a broadcast spreader to apply a lawn starter fertilizer over the area where sod will be laid.
- Add lime or sulfur to soil as necessary, to correct pH.
- Spread this lawn starter fertilizer over the soil at product label rates.
- Mix the soil amendment and fertilizer into the top 2–3 inches of soil using a tiller, rake, or hoe.
By applying fertilizer and natural pH balancing ingredients to your lawn, you simultaneously provide nutrients to your soil and allow your sod to soak these nutrients up once it takes root. Think of this step as providing future growing fuel for your sod.
Level and Add Topsoil
Use a rake, shovel, or box blade to level your yard. It’s much easier to lay sod on level ground. Not only that, but it’s easier to maintain a flat lawn.
- A level grade is key to even watering and healthy grass growth.
- The soil should be 1 inch (2.5 cm) below the top of all paved surfaces.
- Slope the ground slightly away from structures and paved areas, to prevent flooding and poor drainage.
- Add topsoil to low areas as necessary to achieve a level yard.
If your yard has low areas, fill these with additional topsoil. Preparing for sod gives you a chance to create the pristine yard of your dreams.
Use a lawn roller, box blade, or tamper to firm up the dirt. Don’t worry, this won’t undo your tilling work. The soil will be loose enough for grass rooting, but firm enough that it will settle evenly. If you skip this step, your yard may settle in unexpected ways, creating an uneven surface.
- Roll the soil to compact it slightly and prevent uneven settling.
- Use this lawn roller to roll the ground by hand or tow it behind a small tractor.
- After rolling, the ground should be solid enough that footsteps only sink about 1/2 inch (1.25 cm) into the dirt.
Once this step is complete, you’re ready to install your new sod. By putting in the time for soil preparation, all you have to do after sod installation is water and watch your grass thrive.
How Do You Prepare Soil Before Laying Turf?
Before you lay your sod, first make sure to remove all existing grass and weeds with a sod cutter. Then, get rid of remaining rocks and debris in your yard before tilling to a depth of 6 inches. Once initial tilling is complete, perform a soil pH test to make sure the soil is healthy enough for grass. Add any soil amendments necessary to correct unhealthy pH and mix in a lawn starter fertilizer. To finish off sod preparations, level your lawn and use a lawn roller to make sure the soil is firm and settles evenly.