What’s the Difference Between Topsoil and Potting Soil?

In 2021 a little over 18 million people joined the ranks of gardeners. This all adds up to many newcomers asking, what exactly is topsoil and how do I know if I need it?

If this sounds like you, you’re in the right place. Continue reading to learn about the differences between topsoil and potting soil and the gardening applications of each.

What is Topsoil?

In the context of landscaping, the definition of topsoil is actually in the name; it refers to the soil “on top.” This is usually the first six inches of soil where plant roots and vegetation inhabit and is made of clay and rock fragments. It may also often have had manure and compost mixed in; however, its exact makeup varies depending on where the soil is from and what (if anything) used to grow there.

Topsoil is harvested from fields past their growing season, and all the rooty and weedy and microbial bits contained in that top layer are all scraped and packed away as topsoil. If you’ve ever purchased topsoil, you’ll have noticed some root and rock fragments.

The best option for finding topsoil suppliers is by checking with your local landscaping company. To find the best one near you, try searching for “topsoil for sale near me” with your device set to allow it to access your location.

How is Potting Soil Different?

Potting soil is really a misnomer since it contains no soil at all. Instead, potting soil is made up of a nourishing mix of still decaying organic materials that are perfect for encouraging plant growth and fruiting. These often include peat moss, broken-down tree bark, and coconut fiber. 

Since there is no soil in this mix, it is far lighter than topsoil, and due to its specialized content, you wouldn’t use this in large quantities. 

Topsoil Vs Potting Soil: Which to Use for Your Garden Project

Topsoil is heavy and dense and so will retain water and compact very well. However, landscaping topsoil is often nutrient-poor and not the best medium to grow in. Instead, topsoil is used as a filler.

For example, if you’re interested in removing a retaining wall from your backyard, you will need to replace all of the soil that used to make up the natural slope. To accomplish this, you would use topsoil to fill in where the landscape used to be. Generally, anytime you need to replace soil, be it to refill a pond or amend storm damage, you need topsoil to get the job done.

Alternatively, potting soil is nutrient-dense, but because it doesn’t contain any soil, it dries out very fast. This makes it perfect for use in container gardens.

However, keep in mind that some potting soils are for use in containers only. For example, Miracle-Gro potting soil indicates that you should not use this specific product for in-ground planting. 

Ready to Get Your Hands Dirty?

Now that you know the difference between topsoil and potting soil, you can start your next project with confidence. But some jobs (and soils) require an expert opinion, so don’t be afraid to reach out to one if your soil isn’t performing. 

If you liked this article, make sure you continue exploring other informative reads in our Home and Garden sections.