What Does Healthy Soil Actually Mean?

Why soil health is less about finding the perfect soil — and more about learning how soil functions.

I didn't come to soil health because I had a green thumb.
Quite the opposite.

I had made compost before without thinking much about what went into it or what was actually happening inside the pile. And before I tried growing my first plant myself, I wasn't particularly interested in understanding soil either.

What changed that wasn't a sudden love for homegrown lettuce. It was the experience of trying to grow something from the beginning — and realizing how many things had to work together for that plant to thrive.

The plant was what I could see. But more and more of my questions led below the surface.

What makes one soil support growth better than another? What is actually happening in compost? What does “healthy soil” mean — beyond being dark, crumbly and full of earthworms?

When I started researching the first Field Notes guide, I expected that last question to have a fairly straightforward answer.

It doesn't.

Or at least, not in the way I expected.

A healthy soil isn't a particular kind of soil

The more I read, the more one word kept coming up: function.

That changed how I thought about the question.

The USDA Natural Resources Conservation Service describes soil health in terms of how well a soil performs its functions — and whether it can continue to perform them over time. Soil supports biological activity, regulates the movement of water, stores and cycles nutrients, and provides the physical environment in which roots and countless other organisms live. Natural Resources Conservation Service

So asking whether a soil is healthy isn't quite the same as asking whether it looks like the soil we tend to associate with a productive garden.

Dark, crumbly soil may give us useful clues. So might earthworms, deep roots or water disappearing quickly after rain.

But none of them tells the whole story.

And perhaps more importantly, not every healthy soil has to look the same.

A sandy soil will never behave exactly like a clay-rich one. A soil beneath perennial vegetation has a different context from a vegetable bed that is cultivated every year. Climate, parent material, topography, vegetation and management all contribute to what a particular soil can become.

The FAO makes a useful distinction here: soil health can be considered against an abstract "ideal" soil, but it can also be assessed relative to what that particular soil needs to do in its actual setting. A shallow, slightly acidic soil, for example, may be entirely appropriate beneath the vegetation adapted to it while being poorly suited to intensive cropping. FAOHome

That seems obvious once you read it.

It wasn't something I had really thought about before.

Looking for clues instead of a verdict

This also helped me understand why there isn't one definitive soil-health measurement.

Soil health itself isn't something we can directly put on a scale. Instead, researchers and practitioners use indicators: physical, chemical and biological properties that tell us something about how the soil is functioning. Natural Resources Conservation Service

Some of them require proper measurements or laboratory analysis — pH, organic matter, electrical conductivity or microbial activity, for example.

Others begin with observation:

How does water enter the soil?
How is it structured?
Where are the roots going?
Is the surface crusted or protected?
What signs of life can be found?

These aren't replacements for soil testing, but a single observation isn't a diagnosis. They are clues.

That distinction became important while I was putting together the first Field Notes guide.

The guide isn't designed to tell someone that their soil is good or bad. It asks you to look at several things that are connected to soil function, record what you find, and compare those observations rather than trying to draw a conclusion from one perfect — or imperfect — sign.

That approach isn't just a convenient simplification for a field guide. Formal soil-health assessment also relies on combinations of indicators rather than a single outcome. NRCS recommends looking for patterns and comparing observations between locations or over time. Natural Resources Conservation Service

And that makes soil considerably more interesting.

The compost pile I wasn't really watching

I had actually been observing one of these systems long before I started thinking about soil health.

I made compost.

But at the time, I wasn't particularly thoughtful about what went into it. Organic material went onto the pile, time passed, and eventually something very different came out.

I knew what compost was. I just wasn't asking many questions about the process.

Looking into soil biology later made me reconsider something I had already watched happen.

Decomposition isn't simply organic material disappearing. Soil organisms are involved in breaking down organic matter and cycling nutrients, and biological activity is intertwined with soil structure and other soil functions. NRCS therefore includes biological indicators alongside physical and chemical ones when assessing soil health. Natural Resources Conservation Service

I don't think I needed to understand all of that to make compost.

But understanding a little more changes what I notice now.

And I think that distinction matters.

You don't need to become a soil scientist before you can start paying closer attention to the soil beneath your plants.

One observation leads to another

Water is a good example.

You might notice that after heavy rain one part of a garden absorbs water readily while another develops puddles or runoff.

That's an observation.

The explanation is another matter.

Water movement can be related to soil structure, pore space, compaction, surface crusting and other properties. Physical indicators such as infiltration, bulk density and aggregate stability are therefore used to understand aspects of how water and roots move through soil. Natural Resources Conservation Service

The puddle itself doesn't tell you precisely why it happened.

It tells you where to look more closely.

The same applies underground. Roots that suddenly change direction can be worth investigating, but one plant isn't enough to diagnose a compacted layer. An earthworm is evidence of an earthworm, not proof that everything beneath the surface is functioning perfectly.

This sounds almost disappointingly cautious. I actually find it liberating. You don't have to classify your soil immediately. You can observe it.

Regenerative doesn't have to begin with an intervention

This matters to me in the context of regenerative agriculture and permaculture because it's very easy to encounter a practice before understanding the problem it's supposed to address:

Mulch, compost, cover crops, reduced tillage, living roots, greater plant diversity for example.

There are good reasons these ideas appear repeatedly in discussions about soil health. But learning about a regenerative practice and understanding what is happening in a particular piece of soil aren't quite the same thing.

What is actually happening should inform the choice of practice.

For someone with a garden, homestead or field, that can mean beginning with surprisingly simple questions:

What happens here after rain?
Where does the soil remain bare?
How easily can roots move through it?
What changes between one season and the next?

Not because observation gives us every answer, but because it gives the next question somewhere to begin.

Healthy soil is a process, not a picture

I started with an image of what healthy soil was supposed to look like.

I'm leaving the question with something less tidy, but more useful.

Healthy soil isn't one colour, one texture or one number.

It's soil performing a collection of interconnected functions within a particular place.

And because many of the properties we associate with soil health respond to management and environmental conditions, the useful question isn't only What is my soil like today?

It's also:

What is changing?

That is why returning to the same place matters.

NRCS guidance on soil-health assessment explicitly recommends comparing measurements and observations over time or between comparable locations. A single observation gives you a snapshot; repeated observations can begin to reveal a direction. Natural Resources Conservation Service

That idea has probably become the most important one for me while working on the first Field Note:

Look. Record. Come back. Compare.

You don't have to understand everything beneath your feet before you begin.

You just have to start noticing it.

Take it into the field

Field Notes · Issue 01 — Your Regenerative Soil Field Guide takes that idea outside.

It contains five simple field checks for observing soil structure, visible soil life, water movement, soil cover and roots — using your hands and eyes rather than trying to turn those observations into a laboratory diagnosis.

The important part isn't finding five "good" results.

It's connecting the clues, noting the context and returning under similar conditions to see what changes. That's also why the guide ends with “Recheck · Compare · Learn” rather than a soil-health score.

Get the free soil health guide →