Don't Underestimate the Importance of Soil in a Garden

Soil is far more than just dirt. Treating soil like dirt is one of the worst things we can do. If you underestimate the importance of soil in a garden, there is little chance of creating a successful and productive garden which can stand the test of time.

As a gardener, and through my design and consultancy work, I have found that a lack of understanding about soil and its importance is a common cause for garden issues. Many of the most common gardening mistakes revolve around this key issue.

What Is Soil?

If you are new to gardening, you may not have given much thought to what soil actually is. You might think about soil as the stuff below your feet, the stuff which fills garden beds, or is tracked into your home on the soles of shoes.

But new gardeners—indeed, everyone—should understand that soil is so much more than the material we see. Soil is a living ecosystem, teeming with life. Soil is made up of its mineral constituents, organic matter, air, water and living organisms—from earthworms and larvae to nematodes and microscopic bacteria and fungi.

The Importance of Soil

All of these elements combine to create a precious world that is essential to life on earth. Without the complex web of life in healthy soil, the world's terrestrial ecosystems cannot survive. I remind my clients that healthy soil is required to grow healthy plants, and without healthy plants the lives of humans and other animals are no longer possible. In many senses, everything comes back to the soil.

As the UK government states, “The soil delivers 95% of global food supplies, but it is a limited resource under pressure from climate change, population growth, urban development, waste, pollution... and a lack of understanding.”

How Soil Is Damaged and Degraded

The problem is that humanity has already damaged the world's soils to a terrifying extent. Globally, around 30% of land area is already significantly degraded. 

There is an increasing understanding that soils must be protected. The United Nations Sustainable Development Goal 15 has a target to restore degraded land and soil and achieve a land degradation-neutral world by 2030. But monocrop agriculture and other issues around the world mean that in certain areas fertile topsoils could be eroded and damaged to a degree that they can no longer produce viable harvests.

Time is running out to prevent global catastrophe—not just from climate change but also from soil degradation and biodiversity losses. Soil forms only very slowly, and it is being eroded or degraded more quickly than it can be replenished.

Soil degradation is a major contributor to global warming. But repairing our soils has the potential to aid in tackling the climate crisis. As gardeners, we have a responsibility to safeguard the soils on our own properties, and we all have the duty to avoid contributing to harmful systems which further degrade the world's soils.

How to Protect the Soil in Your Garden

I tell clients that it is easier than one might imagine to protect and enhance the soil in a garden. Soil science may be complex, but you can help ensure healthy soil in your garden through a few simple practices. Here are some of my key recommendations:

• Garden organically. Avoid the use of harmful chemicals.
• Avoid digging and tilling. Leave soil undisturbed as much as possible.
• Look to hydrology. Think about catching and storing water in plants and soil. 
• Avoid compaction. Don't step on growing areas.
• Keep soil in growing areas covered, with living plants or organic mulches to prevent nutrient leaching, runoff, and erosion. 
• Retain living roots in the soil over as much of the year as you can. 
• Layer plants in space and time and aim for as much biodiversity as possible. 
• Feed microorganisms within the soil with plenty of organic matter.
• Rotate certain annual crops to prevent nutrient depletion and disease.

Taking a regenerative approach to soils, and truly appreciating the soils below our feet, is essential for a sustainable way of life. As gardeners, we are custodians of soil on our own patches, however small. That is a responsibility that we should all take very seriously.