Why your garden should be no-till (Part 3)

2 specific ways tillage harms your soil, (hopefully) explained for a soil science preschooler like me!

No-till has been all the rage recently.

But my mom’s garden thrived with frequent tillage, so why should I quit tilling?

If you haven’t already read the first two parts of this series, you can read them here and here.

The number one reason I value no-till is because of the health benefits to the soil.

Let me explain…

Running a tiller through the soil demolishes the entire ecosystem inside the soil, requiring all the soil life to start over from ground zero.

Soil is filled with living creatures. In fact, a teaspoon of healthy soil can contain a billion microbes of thousands of different species!

If you’ve ever lain face down on the ground and peered through the blades of grass in your yard (yeah, I actually do that), you were in awe at the number of tiny critters bouncing through their ‘forest’, finding food, eating each other, and just generally living their lives beneath your feet every day.

And if you’re a true gardener, you already know the delight of reaching into your soil and seeing a half dozen earthworms racing for shelter.

Your soil is a thriving city, populated by earthworms, bugs, and all kinds of microscopic and macroscopic critters.

Now imagine that city is New York City, and suddenly a giant tiller came smashing through, chopping and pulverizing everything in its path. Only remnants of buildings are left behind, electric and water infrastructure is ruined, and only a few survivors remain.

The few that remain are left to rebuild the entire city.

In fact, every spring, and sometimes multiple times a year, that same tiller wipes out all the infrastructure, leaving only the survivors to rebuild everything.

Not a perfect analogy, for sure, because microbes can reproduce in minutes whereas humans take years.

But the concept remains.

Every pass of a tiller through the soil destroys an entire city of living beings and their infrastructure, requiring everything to be rebuilt from scratch.

But why is this a problem?

Here are two problems that tillage creates for soil health:

*WARNING! Put on your your thinking caps, we’re about to get a little nerdy.

1. Tillage releases carbon from the soil

Big word of the day = “aggregates”

Repeat after me… ah’ - gruh - gayts

A healthy soil has tiny little structures called “aggregates”, and for our purposes, I’m going to call them carbon houses.

Because that’s what they are, tiny little structures made of soil and built by microbes to house carbon. The microbes use a sticky substance they create to bind the tiny particles together and build these houses, which can range in size from microscopic to a few millimeters. In return, these structures act as houses and food storage for the microbes.

Cool, huh?

I’ll bet you didn’t know the soil below you was full of little construction workers building houses.

So why does all this matter? Three reasons…

• The “carbon houses” (i.e. aggregates… remember that big word?) give soil a loose structure, what some call a good “tilth”. Do you know the feeling of reaching into a beautiful loose soil? Provided it wasn’t just tilled (which creates a short-lasting fake tilth), that’s a soil with healthy aggregation, giving it a beautiful loose structure for growing.

• The “carbon houses” (i.e. aggregates) hold water. A soil with good aggregation will both absorb more water more quickly, preventing run-off and erosion, and also hold onto that water longer, reducing the need for frequent watering and even staving off potential drought.

• The “carbon houses” (i.e. aggregates) give food and shelter to microbes. Just like we build our own houses and gardens, the microbes are doing the same when they build soil aggregation! This gives them a place to live and work.

Now imagine a tiller ripping through that soil and pulverizing the aggregates. Suddenly, the carbon has lots it house, leaving it exposed to the elements, which in this case is a sudden influx of oxygen and oxygen loving bacteria.

And what happens when carbon combines with oxygen?

You guessed it. Carbon dioxide.

Suddenly, large amounts of carbon leave the soil as carbon dioxide, released into the atmosphere as greenhouse gases.

There’s a thousand more things I could say about this, but they’ll have to wait for another time. For now, remember this…

Tillage releases excessive carbon from the soil, turning it into greenhouse gases (i.e. carbon dioxide) that escape into the atmosphere, while reducing the soil’s ability to hold and store water and nutrients, and also destroying the microbe cities that keep your soil healthy and resilient.

Okay, brace yourself, we’ve got one more…

2. Tillage destroys mycorrhizal fungi

Second big word of the day, “mycorrhizal”

Repeat after me: my - coh - riez’ -uhl

What is mycorrhizal?

In Greek, myco means ‘fungus’ and rhiza means ‘root’. Thus, mycorrhizal is a specific strain of fungus that comes together with plant roots to form a beneficial relationship.

Mushrooms are a fungus, remember? Technically, they’re the fruiting body of a fungus, as the body is made of many many feet of mycelium, an underground network of fine white filament that forms a large web under the soil. In fact, a handful of healthy soil can contain over 20 miles of mycelium, and much of that is mycorrhizal fungi! Most mycelium is microscopic, but some can be seen with naked eye.

Mycorrhizal fungi accomplish far beyond what I can even begin to write about here or than what we even know.

But for our purposes, let’s look at the basics…

Picture the mycorrhizal fungi as a giant underground root system that extends far beyond the roots of the plant, vastly increasing the surface area from which that plant can extract nutrients. Just like the microbes mentioned above, mycorrhizal fungi also help hold the structure of the soil. And they can even communicate with other plants to share nutrients and warn of incoming pests or diseases!

Now imagine taking a tiller through a giant web and watching that web shred to pieces. That’s exactly what happens when your tiller rips through your soil.

To add to the loss, mycorrhizal fungi take much much longer to rebuild than the microbial cities mentioned earlier, and they also tend to live closer to the surface of the soil.

In other words, they’re much less resilient to disturbance.

All this to say, any type of tillage has massive implications for the mycorrhizal network in soil, and therefore for the possibility of plants in that soil to reach their full potential.

Again, I’ve only skimmed the surface of all these topics. To dig deeper, check out this video series by Michael Phillips, as well as his book Mycorrhizal Planet. Also consider the books Teeming with Microbes and Teeming with Fungi by Jeff Lowenfels.

In summary, remember this. Any type of tillage destroys at least a part of your soil ecosystem, and destruction takes time to rebuild. This doesn’t mean you won’t be able to grow plants, even healthy plants. However, plants grown in soil sustained by healthy microbiology and mycorrhizal networks will always have a higher maximum potential for nutrient-density, flavor, yield, and pest and disease-resistance.

So if you want to grow healthier plants, try switching to no-till.

And now two disclaimers…

1. No-till is a long-term game, not a quick fix. It takes time to rebuild what was lost. Tillage has diminishing returns, while no-till has increasing returns. Avoiding tillage, at least excessive and deep tillage will allow that network of life in the soil to slowly rebuild, and over time, your plants will have the potential for greater and greater nutrient density and disease resistance.

2. I’ll be the first to admit there are times and places for tillage. More on that another time. No-till is not the end goal, but simply a means to an end. Don’t get dogmatic about it. Used appropriately, limited tillage can sometimes expedite the process of creating healthy soil.

Okay, are you ready to garden without a tiller?

Be on the lookout for 1-2 more posts on why your garden should be no-till.

And if you’re still not convinced by then, …well …you’re still welcome here. I won’t hate you are judge you. I’ll still have loads of good gardening tips that help make gardening easier for you.

Speaking of gardening tips, maybe you’re ready to switch to no-till but don’t know how.

Or maybe you simply want more tools for managing your already no-till garden.

Sit tight, because I have a treat coming for you!

Next week, I’ll start a series for paid subscribers on how to start and maintain your no-till garden, outlining three different no-till methods we’ve used in our garden.

I’ll give you the exact practical steps you can follow in your context to start a brand new garden using no-till methods, or to switch your current garden to no-till, basing it on a short course I made with

JustFarmerJulie

a few years ago.

Until then, happy gardening!

-Laverne