When establishing a new yard from sod, it’s best to prepare the yard with a mixture of topsoil and compost. These two elements should be mixed in together at a ratio of 5 parts topsoil to 1 part compost. This mix will combine nutrient-rich compost with topsoil at the optimal rate.
- Think of compost as a natural fertilizer—it’s full of nutrients. It’s like the sugar in a cake recipe. A little goes a long way.
- Topsoil is the ingredient that holds and distributes the nutrient-rich compost evenly. It’s the flour in the cake recipe.
By mixing compost and topsoil you provide a nutrient boost to your new soil and set yourself up for easy lawn maintenance in the future. If you were to use only topsoil, it may not have enough nutrients to sustain grass. If you use only compost, not only would it be much more expensive, you could potentially overload your grass with too many nutrients.
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What is the Difference Between Topsoil and Compost?
Topsoil is dirt removed from a building site. It typically contains rock, clay, sand, wood chips, and some nutrient-packed loamy organic materials. Compost is nearly all loamy organic materials. This organic material feeds plants and grass.
- Topsoil is dirt, mixed with rocks, clay, and sand. It may have some organic matter/nutrients.
- Compost is decomposed organic matter from vegetable waste, manure, and other sources. It is chock full of nutrients for your grass.
So, the topsoil you order may have a little composted material already in it, but odds are it isn’t enough to feed a lawn and promote good sod growth. This is why you should add compost to ensure your sod gets what it needs to thrive and take root fast.
Is Compost Good for Sod?
Compost provides nutrients that sod needs for initial growth and long term health. It’s an excellent soil additive that boosts the quality of whatever dirt it is mixed with.
- Compost boosts soil nutrient levels essential for grass root and blade growth.
- Compost is a natural fertilizer. Like all fertilizers, too much can harm grass.
Fertilizer overload is not good for grass, and the same rule applies for compost. Too much of the nitrogen in compost can pull the moisture out of your sod, causing it to dry out and die. Compost and other fertilizers should be applied in controlled quantities. This will provide benefits without drawbacks.
Should You Use Topsoil or Compost for Sod?
The best course of action is to use both topsoil and compost. The key is to mix topsoil and compost application together. This will imbue your soil with nutrients at the proper levels for healthy growth.
- Topsoil is relatively inexpensive. Good, dark topsoil should be used to replace clay or sandy soil in a yard.
- Good topsoil is a foundation that is further improved by mixing in compost.
- Compost is more expensive than topsoil. You’ll save money and get better results by mixing compost with topsoil.
It’s essential to include both good quality topsoil and organic compost as part of the soil preparation for sod. This will ensure a low-maintenance lawn for years to come.
How to Use Compost and Topsoil with Sod
To prepare your lawn for sod using a mixture of topsoil and compost, it’s essential to do the following:
- Plan to add 4 inches of topsoil and compost mix to your yard, to create a foundation for new sod.
- Spread 10 cubic yards of topsoil per 1,000 square feet of yard.
- Spread 2 cubic yards of compost per 1,000 square feet of yard.
- Use a rototiller to mix the compost and topsoil together.
This foundation can then be finished off by rolling, leveling, and finally installing your sod. This layer of compost and topsoil serves as a bed for the sod to send deep roots into.
How Many Inches of Topsoil Do You Need for Sod?
New sod performs best when laid on top of 4 inches (10 cm) of topsoil and compost mix. This provides a deep bed of loosened earth that the sod can send roots down into. From there, the grass will begin to gather nutrients and water, making it resistant to drought and disease.
- 4 inches of topsoil and compost mix is best for new sod lawns.
- For extra depth and hardiness, plan to add 6 inches of topsoil and compost mix.
A layer of soil 4 inches deep is perfect to prepare most yards for new sod. However, if the ground beneath the new topsoil is extremely hard rock or clay, you may want to spread a 6-inch layer of topsoil and compost mix.
What is the Best Ratio of Compost to Soil?
Spread 5 parts topsoil to 1 part compost for best results. This 5:1 ratio will keep costs manageable and add a healthy amount of nutrients to your soil. Your sod will feast on this soil.
- A 5:1 ratio of topsoil to compost is best for new sod.
- To achieve a 4-inch layer for sod, spread 10 cubic yards of topsoil and 2 cubic yards of compost per 1,000 square feet.
- For a 6-inch layer beneath your sod, spread 15 cubic yards of topsoil and 3 cubic yards of compost per 1,000 square feet.
Before ordering topsoil and sod, first, measure all areas of your yard where new sod will be laid. Then, calculate the square footage. Finally, order accordingly. Some suppliers may deliver partial yards if requested.
What Goes First: Compost or Topsoil?
It’s best practice to spread your topsoil first, then lay down a top dressing of compost. Although these two ingredients will be mixed in the following step, more of the compost will remain near the top of the mix. This provides a really useful initial boost to new sod.
- Spread topsoil first, then compost.
- If possible, mix compost into soil soon after spreading. Compost exposed to direct sunlight may lose some of its nutrients.
Many composts are made from manure, which delivers plant-fueling nitrogen in the form of uric acid. While it’s a powerful fertilizer, uric acid evaporates in sunlight. For this reason, it’s essential to mix your compost into the soil to preserve this nutritive value.
How Do You Mix Compost and Topsoil?
Rent or buy a rototiller to mix your compost and topsoil before laying sod. This mixing process will distribute the compost through the soil, providing gradual nutrients as the sod develops deep roots.
- Rototillers can be purchased, or may be available for rent, at your local hardware store.
- Till topsoil and compost together to a depth of 6 inches.
- Work the soil with the tiller until the components are well-mixed.
Whether you laid 4 or 6 inches of new material, till down to a depth of 6 inches. This will break up any original soil still beneath and incorporate it into the mix, allowing for the deep rooting that helps new sod turn into a healthy, established lawn.
Which is Better for Sod: Compost or Topsoil?
Both compost and topsoil are essential for new sod success. For best results, mix 5 parts topsoil with 1 part compost. Spread these materials in a 4-inch deep layer across your yard and till them to mix the components together. The resulting mix is nutrient-rich soil that promotes healthy sod growth from day one onward.
Remember, compost is a natural fertilizer that should be used sparingly to boost the quality of your topsoil. You will get the best yard for the lowest cost with this method.