Dirt is dirt, right? Unfortunately, there are many different types of dirt and if you want the most success in your garden, it’s important to know what you are using. Read on to better understand the types of dirt and what they are best for.
Differences between potting soil, topsoil, and garden soil: Potting soil is used for container gardens as it has some nutrients but creates a light texture to allow roots to move effortlessly. Topsoil has been screened of large objects but only has natural organic matter in it, such as leaves and bark mulch. Topsoil comes from the top layer of the ground and is great for filling in deep areas of your yard. Finally, garden soil is topsoil with extra nutrients added, usually through compost. Use garden soil when creating new gardens.
What is potting soil?
Potting soil is actually a mix of many organic materials and often contains very little actual dirt. Both the nutrient qualities and the texture of potting soil make it ideal as a top layer in your garden or for plants in pots.
Potting soil will contain a mixture of fine mulch and vermiculite, which helps with drainage. It will have a light, fluffy texture to it which allows water to seep through the soil and drain properly.
You will often see pieces of white material in potting soil. This is called perlite and they are volcanic glass.
The purpose of perlite is to increase soil aeration and improve drainage. You do not need to have perlite in your potting soil but it will help your garden overall.
What is topsoil?
Topsoil is a little bit harder to understand, namely because different places have different definitions for it. If you are using topsoil or want to purchase it, it is best to ask a few questions about its origin.
At its most basic definition, topsoil is merely the top layer of soil. This exists everywhere, even in your garden.
However, in an industrial setting, it can mean a deeper dig of dirt that is screened to remove rocks and other debris. If you are looking for a larger amount of dirt to establish your garden, starting with topsoil is a solid idea.
Finally, sometimes topsoil is also called fill. This is not actually true, and the two should not be interchanged.
Fill dirt is merely there to fill in holes and not for planting purposes. You can even find free-fill dirt whereas you will almost always have to pay for topsoil.
What is garden soil?
Garden soil starts out as topsoil but then is enriched. This is what you want if you are putting in a large garden.
Garden soil will have other organic materials mixed into it, such as manure or compost. This will add nutrients to your garden soil so you are starting with a decent base.
There are different grades of garden soil and different mixes and ratios. It is usually the case where the more expensive the price, the more nutrients have been added.
You can purchase bags of garden soil at gardening centers but if you need a lot, the more economical route to take is purchasing it in bulk. You can contact a local company who will drop it off on your front lawn or driveway and you can then use it as needed.
Difference between topsoil, garden soil, and potting soil
Gardening is all about planning. The more you can plan, the better your garden will turn out.
It also will mean less work for you in the long run as it will mean you don’t have to dig plants up and move them around. Planning will also help create a healthy garden.
If you have a larger hole in your yard, say if you are removing a deck or taking out a large tree stump, then filling that in with topsoil is the best option. The topsoil will still be decent-quality dirt and will help stabilize the area.
However, if you have a large area that you are converting into a garden, then starting with garden soil is best. When doing this you have two choices.
If the current dirt in your yard is okay, you can merely dig it up and add in garden soil and mix it up. This will save you money and labor.
However, if your current dirt is compacted, full of clay, or has no nutrients left, then you may want to dig it up and remove it altogether. Then you will need to spend more money on garden soil to fill it back up to the level you want.
Finally, if you have a small container in which you want to plant flowers or vegetables in, then use potting soil. Containers need soil that is able to stand alone, which potting soil can do.
The perlite or other substances in potting soil will ensure there is proper drainage, which is important in smaller containers. It will also have nutrients built in to sustain the new plants.
Type of plants
For the most part, topsoil isn’t recommended if you are planting any sort of plants. Unless you add nutrients to it, it won’t be a good base to start the growing process.
If you are filling in a yard, you can start with topsoil and then add a layer of garden soil before planting your grass. This is more economical and will work just fine as the grass is pretty hardy.
Any vegetable garden should start with garden soil. It will have nutrients added that will support the growth of your vegetables. Likewise for a flower garden, starting out with decent garden soil will help your plants grow and bloom.
Use potting soil for indoor plants, although if they are tropical you may want to find tropical potting soil. Generally, potting soil isn’t used for vegetables, even if you are planting them in a container.
Topsoil has some nutrients in it, but this is from nature and not added in. Think about the natural state of the outdoors.
Fallen leaves, dead grass, and bark mulch all form part of topsoil and as these organic pieces break down, they leave behind precious nutrients.
Garden soil starts with these natural nutrients but then more is added. In the form of compost or other organic matter, garden soil is more nutrient-dense.
You should use garden soil that doesn’t have any fertilizer in it. This way you can choose if you want to use chemical fertilizer or something organic, such as compost or manure.
Potting soil is heavily made up of bark mulch, which has plenty of nutrients. It might have other organic materials to increase its nutrient density.
Whichever type of soil you need, the nutrients will eventually diminish. It is recommended to apply new compost to your soil once or twice a year to re-build these nutrients.
For specific vegetables and plants, you can also use chemical fertilizer. This needs to be specific to the plant as they will need a different ratio of nitrogen, phosphorus, and potassium.
The smaller the amount, the more expensive the soil will be. This is true, at least when compared to bulk orders.
Potting soil is only found in bags, so it can be very expensive if you need a lot of it. In contrast, topsoil is often only found in bulk deliveries. Garden soil can be found in both bags and bulk delivery.
Within each category of soil will be further subcategories. If you have garden soil that has a higher ratio of compost in it, this will increase the price.
Likewise, if you have potting soil made for specific purposes, such as tropical plants, this can result in a higher price tag.
It is always cheaper to have your soil delivered to you. You might not think you need so much, but the thing with soil is that once you spread it around your garden, it quickly disappears.
Another option is to check with your neighbor if they need any topsoil or garden soil. Then, you can split the price difference.
Finally, if you have access to a truck, you can forego the delivery fee for your soil. For smaller orders, sometimes the delivery fee is as much as the actual soil price.
How to know what type of soil to use?
When in doubt, always ask your local gardening center. They will tell you the type of soil to use in addition to the recommended brands.
When purchasing new plants, take this time to research the soil needs. Some plants have dense root structures, so they will thrive in heavily aerated potting soil. In contrast, some plants don’t need a lot of space for their roots, so will do fine with topsoil or a mixture of topsoil and garden soil.
We hope you now have a better understanding of the difference between topsoil, garden soil, and potting soil. Use topsoil for large-fill projects, garden soil for establishing gardens, and potting soil for containers.