Garden Soil vs. Top Soil (What Is The Difference?)


If you are starting or expanding your garden this year, then you probably want to add some soil to your yard.  In that case, you might be wondering what sets garden soil apart from top soil, and if the difference really matters.

So, what is the difference between garden soil and top soil?  Top soil is naturally occurring, while garden soil has been carefully cultivated by gardeners for growing desired plants.  Top soil will contain some organic material and nutrients, but garden soil has been amended with compost or aged manure to add even more organic material and nutrients.

Let’s get into more detail about each of these types of soil and when to use each one.  We’ll also answer some common questions about top soil and garden soil.

What is the Difference between Garden Soil and Top Soil?

The main difference between garden soil and top soil is the fact that garden soil is cultivated by gardeners for growing specific plants.

Top soil is naturally occurring, and it is likely to contain rocks, sticks, soil clumps, and other debris.  It is found on the ground all over the planet, except where it has been eroded by natural forces (wind or water).

rocky soil
Top soil contains lots of rocks, since it is naturally occurring and has not been cultivated for gardening.

Top soil can have many different structures: light sand, dense clay, or something in between.  It will contain some organic material and nutrients, but it has not been custom-made for gardening and growing plants.

Top soil is not really cultivated, prepared, or “made” – it simply exists, as it has for many years.

On the other hand, garden soil is carefully cultivated by gardeners for the purpose of growing plants (often vegetables and herbs for the kitchen!).  Garden soil usually contains some topsoil, but it also contains extra organic material (from compost or aged manure).

Compost
Garden soil is rich in nutrients and organic material, since it has been cultivated over time for use in growing vegetables, herbs, and other plants.

Often, the debris mentioned above (rocks, sticks, soil clumps, etc.) has been sifted out of garden soil over time.  This leads to smoother soil, which means plants (especially root crops like carrots and potatoes) will grow better.

Garden soil is an improvement on topsoil for two main reasons:

  • Garden soil contains more organic material, so it drains better than clay in wet weather, while also holding more water than sandy soil during dry weather.
  • Garden soil attracts more beneficial soil organisms, such as earthworms and bacteria.  These organisms help to loosen the soil and add air and nutrients.  They also break down organic matter (leaves, grass clippings, etc.) and turn it into a form that plants can use to get the nutrients they need to grow.

The composition of your garden soil will vary, depending on many factors:

  • The type of organic material used as an additive (compost, aged manure, fresh manure, etc.)
  • Fertilizers and other nutrient supplements used in your garden.
  • The texture of the topsoil used as a “base” for your garden soil.

What is Topsoil?

According to Wikipedia, topsoil is the uppermost layer of soil, consisting of the top 5 to 10 inches (12.5 to 25 centimeters).  Topsoil contains minerals, organic matter, water, and air. The amounts of each will depend on the type of soil and climate conditions.

There are many different types of top soil, but the two extremes are sand and clay.

Sandy soil has large particles that do not stick together easily.  Sandy soil tends to be smooth and light, and it drains well (sheds water).

sandy soil
Sandy soil is smooth, has large particles, and drains well.

Clay soil has fine particles that stick together easily.  Clay soil tends to be dense and heavy, and it drains slowly (holds water).

clay soil
Clay soil is heavy, has fine particles, and drains poorly.

There are many types of top soil between the sandy and clay types, but the main differences will be in drainage (water retention), air, minerals, and organic matter in the soil.

What is Topsoil Used For?

Top soil has many potential uses, but is most often used to level off the land in your yard.  For example, you could use topsoil to fill in holes in your backyard to avoid twisting an ankle!

You can also use top soil to smooth out a steep slope that would otherwise prevent gardening or cause flooding.  In addition, top soil can be used to even out the ground for laying the foundation of a shed, barn, or garage.

Top soil is also used in construction projects and landscaping.  Since it is more abundant and less nutrient-dense than garden soil, it is better to use top soil for the purposes mentioned above, rather than wasting your precious garden soil.

How to Protect and Preserve Topsoil

Top soil is prone to erosion in some areas, due to wind or water combined with a lack of trees or shrubs (the roots of these plants help to hold the soil in place).  You can learn more about soil erosion (and how to prevent it) here.

One good way to prevent soil erosion is to use green manure (cover crops), such as alfalfa, during the “off-season” when you are not growing vegetables in your garden.

Green manure crops will restore nutrients to the soil.  Their roots will help to hold the soil in place, preventing erosion of top soil and garden soil alike.

alfalfa
Green manure (cover crops) such as alfalfa (Lucerne) help to restore nutrients and prevent soil erosion.

The best part is that green manure crops can be harvested and fed to animals, or tilled into the soil to provide nutrient for next year’s garden!  You can learn more about the benefits of green manure here.

Can You Use Top Soil in a Raised Bed?

No, you should not use plain top soil in a raised bed.  You should use garden soil in your raised bed instead.

This means taking a few important steps to improve the soil:

  • Sift the top soil to remove rocks, sticks, roots, dirt clumps, and other debris.  Smooth soil is much easier to work with a trowel or shovel.  Smooth soil is also better for growing root crops, such as carrots and potatoes, since they like to grow freely without running into obstructions.
  • Amend the top soil with organic material, such as from compost or manure.  This extra organic material will improve the drainage and water retention ability of the soil.  It also attracts beneficial organisms like earthworms and bacteria.  You can make compost from yard waste (grass clippings, fallen leaves, etc.) or kitchen scraps (banana peels, orange rinds, etc.)  You can learn how to make your own compost here.  If you decide to use manure, make sure that it ages properly first.  Manure that is too fresh will have too much nitrogen, and can burn plants.
  • Add fertilizer or other supplements to provide your plants with the nutrients they need.  This could mean using NPK fertilizer (such as 10-10-10), lime (calcium carbonate), Epsom salt (magnesium sulfate), chelated iron, or others.  However, before you add any of these, get a soil test to make sure the soil really needs it!  You can learn more about soil testing here.

What is Garden Soil?

Garden soil is the smooth, nutrient-dense, well-draining soil that gardeners use to grow vegetables (or other plants) in the garden.  Many gardeners will carefully cultivate their garden soil for many years by removing rocks, adding compost or aged manure, and rotating their crops to avoid nutrient deficiencies.

Garden soil will usually contain some top soil from your yard, but it is much better suited for growing plants.  Since garden soil is rarer and more difficult to find than top soil, you should avoid wasting it for generic projects like filling in holes or leveling out your yard (use top soil for that!)

What is the Use of Garden Soil?

You can use garden soil to fill plant containers such as pots, grow bags, and raised beds.  Garden soil provides a good growing environment for mature plants after they pass the germination and young seedling stage of development.

supported raised bed
Garden soil is useful for filling pots, grow bags, or raised beds for growing vegetables, herbs, and flowers.

What is the Best Type of Soil for Gardening?

According to the University of Maryland, the ideal soil for gardening will contain 20% to 50% organic matter by volume, or 5% to 15% by weight (a soil test can tell you the percentage of organic material in your soil).

The ideal soil for gardening will be somewhere between sandy soil and clay soil.  It will drain well in wet weather, but also retain some moisture in dry weather.

It will also be easy to work the soil, and it will be smooth and free from debris like rocks and sticks.

Remember: your garden soil will not become perfect overnight!  It will take time and work to improve the soil for your garden.

You will need to add compost or aged manure to improve the structure and consistency of your soil.  Over time, this will attract more earthworms and beneficial bacteria, which will also help to loosen and aerate the soil.

If you have compacted clay soil, use a pitchfork to loosen it up.  Then, add a mixture of compost and topsoil to help improve the drainage and add air over time.

Conclusion

Now you know the difference between garden soil and top soil.  You also know when to use each type of soil, and how to create the optimal soil mix for your garden.

I hope you found this article helpful – if so, please share it with someone who will find the information useful.  It’s time to get back to the garden and improve it with the right soil!

jonathon.david.madore

Hi, I'm Jonathon. I’m the gardening guy (not guru!) who is encouraging everyone to spend more time in the garden. I try to help solve common gardening problems so that you can get the best harvest every year!

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