What’s in Garden Soil: Garden Soil vs Other Soils - Backyard Boss
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What’s in Garden Soil: Garden Soil vs Other Soils

At the start of spring, amateur and expert gardeners alike are faced with a crucial choice: which soil to select for their plants. This is an important decision that will determine how well your plants do throughout the season. While there are two primary types of soil — garden soil and potting soil — they aren’t the only kinds.

Read on to learn what garden soil contains and how it compares to other soils.

The Differences Between Garden Soil and Potting Soil

Each soil has its own purpose and is made of different materials. Garden soil is rich in leftover nutrients from plants and animals and is entirely natural, whereas store-bought potting soil is a mix of ingredients combined at a factory. That said, you can mix your own potting soil to have more control over the nutrients your plants receive.

If you look at the contents of potting soil, you will find that most potting soil mixes are made out of peat moss, compost, and perlite. Meanwhile, garden soil consists of tiny stones, decayed organic matter, as well as some living organisms. Both are fantastic growing mediums; however, they are very different in their purpose.

To determine which you should use, you’ll need to think about what you’re planting. If you want to plant your flowers in the garden, you should go for garden soil; if you’re planning on container gardening, then potting soil is what you need.

Aeration, Water-Retention, and Drainage in Potting Soil and Garden Soil

Terracotta pot with organic soil inside and some outside with green leaf on the old cement floor
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Garden soil typically has void space in between its particles; you should avoid using compacted garden soil because new plants will lack air and water and have difficulty growing their roots. If you have a large amount of compacted soil, you’ll need to loosen it before use. Potting soil, on the other hand, has better aeration and water retention than garden soil because it’s specifically formulated to do so. It can hold enough air and water for indoor plants to thrive.

Density and Weight in Garden Soil and Potting Soil

earth for a plant in a black bag. the soil is black earth fertilizer for gardening
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It shouldn’t come as a surprise that garden soil is quite dense and heavy, since it’s rich in organic matter that has amazing water-retention properties. Unfortunately, this also means that this soil is prone to compaction over time. Potting soil, on the other hand, is light and fluffy. While it still has great water-retention properties, it is at much less danger of compaction. However, if you overwater potting soil, it will start to get heavy.

Contents of Garden Soil and Potting Soil

Soil with bag for planting on wood background and agriculture tool
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Garden soil typically contains a lot of nutrients due to it being full of decayed plant matter. As organic matter breaks down, it becomes bioavailable and thus, garden soil becomes replenished. Moreover, it is full of living organisms such as bacteria, fungi, earthworms, critters, and other bugs. And while this is okay and even encouraged for outdoor planting, using unsterilized garden soil for an indoor plant could lead to devastating results, such as stunted growth or even premature plant death. This is because unsterilized soil is often home to many weed seeds, diseases, pests, and unwanted pathogens.

Lastly, it can contain a lot of seeds, some of which can germinate, causing an explosion of weeds. You can sterilize garden soil, but it’s still not recommended to use it for indoor plants. Contrary to garden soil, the nutrients in potting soil don’t naturally replenish. To do so, you will have to manually add nutrients such as nitrogen to the soil.

Furthermore, store-bought potting soil is often sterile because it is treated with chemicals to kill pathogens, pests, and diseases before it is packed. This means that there should be no seeds or living organisms in it, except for the occasional beneficial mycorrhizal fungi that some mixes choose to add. That said, the age of the packed soil plays a huge role in its sterility. Potting soil can go bad if it isn’t stored properly or if it is left open and unused for over six months.

Pros and Cons of Garden Soil

metal old shovel is stuck in the black soil of the earth in the vegetable garden in the autumn garden during agricultural work
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Whether you choose to use garden soil or potting soil, you should first learn about the pros and cons of each. In the case of garden soil they are:

Pros:

  • Gives a wonderful environment for a thick root base development, due to the way it envelops the roots.
  • It is easy to replenish its nutrients, and it’s eco-friendly. All you will have to do is use your kitchen scraps and add them to the soil. This will make the texture better and the nutrients level higher.
  • The amounts of organic matter it contains will ensure that your plants have loads of nutrients for a long time.

Cons:

  • The pH level will vary and it primarily depends on the location. This is why it is crucial that you test your soil, using a home pH soil test, at least once every couple of seasons. This way, your plants will thrive in a safe and healthy environment.
  • Garden soil will suffocate plants with weaker root systems due to its weight.

Pros and Cons of Potting Soil

Hand holding gardening soil for houseplant
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Pros:

  • Potting soil will retain moisture excellently, which is very important for roots. However, there is risk of root rot if you overwater your plants.
  • Sometimes it contains garden soil. To make sure, check the package label.
  • It contains few ingredients, such as peat moss, perlite, vermiculite, organic matter, and plant material.
  • Most of the time, it has a root activator. This means that the root system will get the boost it needs for growth.
  • You can refresh it easily by adding different nutrients tailored to the plant for which you’re using it.

Cons:

  • It contains much fewer nutrients than garden soil, with one percent or less nitrogen, potassium, and phosphorus.
  • It can compact into a solid block in very warm weather.
  • Store-bought potting soils come with an expiry date that affects their sterility.

Other Soils and Their Uses

Different types of soil as background
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While garden soil, potting soil, and potting mix are three of the most used soils for planting, there are other types of soils you can use, depending on the type of plant you’re growing in your backyard. Here is a brief overview of other types of soils you may come across:

Sand Soil

Texture Sandy and gritty
Pros Drains fast and dries easily Warms up faster than other soils
Cons Not rich in nutrients Needs a constant nutrient boost
Ideal For Potatoes, parsnips, carrots, lettuce, peppers, squash, collard greens, strawberries, tomatoes, zucchini, corn, hibiscus, tulips, tree mellow

 

Clay Soil

Texture Smooth, sticky, and lumpy when wet; hard and rocky when dry
Pros Rich with nutrients
Cons Difficult to grow with Poor drainage
Ideal For Summer veggies, ornamental shrubs, bergamot, aster, quince, Helen’s flower

 

Silt Soil

Texture Smooth and slippery when dry; sticky and greasy when wet
Pros Holds moisture Rich in nutrients and organic material
Cons Lacks proper drainage Lacks soil structure
Ideal For Ideal for most plants, including cypress, birch, willow, dogwood, mahonia, New Zealand flax

 

Chalk Soil

Texture Shallow, stony and chalk-like
Pros Drains well
Cons Alkaline in nature Lack of water retention
Ideal For Beets, spinach, cabbage, sweet corn, lilac, weigela

 

Peat Soil

Texture Damp and spongy
Pros Retains water
Cons Lacks proper drainage Lacks nutrients
Ideal For Legumes, salads, root veggies, witch hazel, heather, camellia

 

Loam Soil

Texture Damp, fine, and moldable
Pros Drains well Loaded with nutrients
Cons Acidic in nature Requires constant nutrition boost
Ideal For Ideal for most veggies and fruits, including bamboos and wisteria

So Many Choices To Choose From

Unfortunately, it is a misconception that garden soil and potting soil are the same thing and can be used interchangeably. There are some significant differences between the two soils and confusing them can be fatal for your plants.

Garden soil is used for outdoor plants, and potting soil is for potted plants. Moreover, these aren’t the only types of soil on the market.

To sum it up, there is no winner in the competition between soils, mainly because they serve completely different purposes. Hopefully, this article was helpful to you! If you have any questions, please leave a comment down below.

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