Myths vs. Facts: Common Misunderstandings About Topsoil

Despite what you might think, not all soil is the same. When gardening, topsoil is the uppermost layer of dirt that you encounter, generally the first two to eight inches of soil on the surface of the planet. Gardeners and non-gardeners alike are often left with questions like What is topsoil made of? and Is all topsoil the same? and may buy into some of the misconceptions surrounding the subject. Separate fact from fiction and learn everything you need to about topsoil with these helpful mythbusters.


Myth 1: Having good topsoil means I don’t have to do any additional work.


While a healthy layer of topsoil will do wonders for your plants, you still need to put in the work to have a thriving garden. If you’re planting annuals or vegetables, for instance, you’ll still need to till the soil as you normally would. Soil can be compacted over time, and not even topsoil is immune to that. Adding one to two inches of compost as you till is still recommended, as it keeps the soil rich and loose.


Myth 2: All topsoil is essentially the same.


Even within the same yard, topsoil can differ dramatically from one area to another. The correction to this myth also answers the question What is topsoil made of?, as variants of topsoil are different because of their specific combinations of components. Sand, silt, and clay all compose topsoil in various proportions. Topsoil also typically contains organic matter, or decomposed plant matter, insects and organisms like earthworms, oxygen, air, and water. In fact, the soil stores approximately 0.01% of Earth’s total water within its pores.


Myth 3: I can use dirt from my yard as a new garden bed’s topsoil.


While doing this wouldn’t destroy your new garden bed, you will need soil filled with organic matter for the best results. The soil already in your yard will likely not have enough organic matter to properly nutrify your new garden bed. It is best to purchase topsoil, till a two to three inch layer into the existing soil, and then layer about five more inches on the top.


When you know how to use topsoil in your gardens, you’re giving your plants the best support they could have. Know that it differs from fill dirt, potting soil, and bagged mulch, and you’ll have a thriving garden.