The Whys and Hows of Topsoil: How to Improve Topsoil Health

This is especially true for your garden. One of the biggest garden mistakes we see as landscapers in the Mornington Peninsula is when homeowners neglect their soil. We've always reiterated how good quality soil provides a fool-proof foundation for the best landscapes, and when you start with a solid base, your garden is already halfway there.

Topsoils are the foundation of your garden that provides the nutrients it needs to thrive. This type of soil is often used to fill in surfaces of your lawns to smooth them out or raise your garden surface higher. It's also used as a base layer for many gardens.

Topsoil vs garden soil: What's the difference?

Topsoil should not be confused with garden soil as they have different distinguishing properties. Let's take a look at the differences between both types of soil.

What is Topsoil

Topsoil is the outermost layer of the ground that's 2-10 inches deep on average. Known for its dark, soft, and loamy soil texture, topsoil has low water retention, allowing air and water to reach its roots. All plants rely on topsoil to thrive, as it is the natural uppermost layer of a garden's surface, and it is simply known as 'soil' to many gardeners.

What is Garden Soil

Meanwhile, garden soil is basically topsoil with added fertilisers, compost, bark, and other nutrients needed for the garden. Generally, garden soils are available in premixed bags that are mixed to satisfy a specific type of garden (i.e. flower or vegetable gardens). If your garden has only topsoil, you would have to add your own fertilisers and organic matter to enrich your soil fertility and health.

Topsoil is an integral foundation for your garden that must be maintained for it to stay alive. Let's take a look at just how much topsoil improves your garden.

Why soil health is important

Soil is one of the biggest contributors to your plant's health. When your soil is poor, this may cause your plants not to grow and even die. Here are some of the properties of healthy soil that are critical to your plants and gardens.

Water drainage

Topsoil that's in good health allows water to drain properly from the soil to the roots. Water that accumulates in the plant root can cause root rot, so it's important to have soil that promotes proper drainage. However, your soil should also be able to hold water instead of letting it run off the surface.

Provision of nutrients
Healthy soil contains a variety of nutrients like nitrogen, calcium, and magnesium, which are needed for a healthy garden. This right balance of nutrients keeps plants from suffering from stunted growth, yellowing leaves, and diseases.

Low soil compaction

Soil compaction is defined as the level at which soil particles are pressed together. The more compact your soil, the more difficult it is for plant roots to grow and water to penetrate the soil. Low soil compaction levels help plants better access the nutrients they need.

Soil pH

Good soil should always have a pH range between 6.0 to 7.5 to promote plant growth. Soil that contains too much acidity or alkalinity can limit its nutrients and growth.

Contains beneficial organisms

Healthy soil generally contains a range of beneficial organisms that help your plants grow. This includes bacteria, earthworms and fungi.

With those considerations of what makes soil thrive, how does one know if the soil in one's backyard is healthy? Fortunately, there are some simple checks to determine this.

Soil fertility: How to tell if your topsoil is healthy or not

Here are a few simple ways to determine if your soil is a healthy base for your garden.

Structure

How does the soil feel? Nutrient-rich soil has different-sized aggregates or chunks that allow water and air to enter the soil and drain easily. However, the soil is also compact enough to hold the right amount of water to maintain plant growth. To test this, dig a 6 to 10-inch hole in damp soil and remove a soup can-sized section to determine its structure.

Earthworms

Earthworms are a good sign that your soil conditions are supportive of growth. Dig a 6-inch deep hole and count the number of earthworms you see for 5 minutes. The more you see, the better it is!

Living organisms like beetles, centipedes, and spiders are a good sign of healthy soil. Just like earthworms, more is better here, so watch your soil for these critters.

Soil Compaction

Is your soil too compressed or hard? Compacted soil will stop plants from getting enough water and nutrients and prevent healthy living organisms from moving around the plant's roots. You can test this by sticking a wire into the soil and taking note of the depth at which the wire bends. It should be able to get through the soil by at least a foot.

Soil Meter

To get a proper reading of your soil moisture levels, consider investing in a soil meter. This handy tool can test your moisture, pH levels, and light to determine if your soil is suitable for your plants.

How to improve topsoil health

Does your soil need a little help? Here are some tips on how you can improve your soil health that supports your dream garden.

Improve Soil Drainage

Adding sand and gravel can improve soil drainage and allow the plants to get enough water. It can also prevent waterlogged soil, which can cause root rot and diseases.

Test and adjust pH

While most plants prefer slightly acidic soil with a pH level between 6 and 7, this number can also vary between plants. Understand your plant's pH levels and adjust accordingly by adding lime to increase its alkalinity or sulfure for acidity. Here's a great video on how we use the Manutec Soil PH Test Kit to test the soil's pH levels

Fertilisers help your garden by providing nutrients that might not be present in the soil. So consider using fertilisers like bone meal, fish emulsion, and chemical fertilisers to improve plant growth.

Use organic soil matter

Soil matter is the living and dead matter that can improve soil moisture and structure. Living matter includes earthworms, bacteria, and insects, while dead matter can be compost and dead leaves.

Mulching

Mulching has many benefits, the biggest being soil moisture and nutrient retention. Mulching also saves time from weeding and watering. Remember to mulch at least 2-3 inches thick (80-100mm), and keep your mulch away from the tree or plant trunk to avoid pests and diseases.

Keep tilling to a minimum

Deep and regular tilling can disrupt the food web and soil structure. Try to keep it to a minimum or eliminate it altogether to ensure that microorganisms and soil properties like earthworm burrows, pore spaces, and soil aggregates remain intact.

Key Takeaway

The journey to your ideal garden begins with good soil, so don't forget to show it some TLC before starting your next landscaping project. For additional help in improving your soil health and creating a beautiful outdoor space, Foliage Landscaping is here to help.

For more than two decades, Foliage Landscaping has helped homeowners in the Mornington Peninsula turn their gardens into sanctuaries for family and friends. To learn how we can improve your outdoors, request a free quote today.