What Are the Best Reasons to Use No-Till Gardening?

Have you ever wondered what happens in the soil when you break it up with a roto-tiller or plow?  These gardening tools cause a catastrophe as they move through the soil.  To avoid this, we can use no-till (also known as no dig) gardening methods.  Let’s embark on a journey to discover what no-till gardening is and how tilling vs. no-tilling compares.  We’ll also find some great benefits from no-till gardening.

What is no-till gardening?

The basic idea behind is to leave the soil alone.  Instead of turning the soil with a shovel, plow, or tiller, you build your garden bed on top of the existing ground.

This method is a key part of every successful organic gardener’s playbook. It preserves life in the soil and encourages continued plant growth.

Even large farms are using more no-till methods.  The USDA reports that over 50% of US farms have changed to no-till farming.  Studies show that no-till farming:

• Prevents erosion.
• Uses less fuel and equipment.
• Minimizes weeds.
• Promotes soil health.

Tilling has been the method for many gardeners and farmers for millennia, but why?  Consider what happens in nature.  Every year, seed-bearing plants drop their seeds on the ground during the fall.  This happens with plants from maple trees to parsley.

Through the winter and early spring, some seeds die, and some feed wildlife. The ones that remain sprout into new plants when the weather warms up.  When you look at the vast number of plants in nature, you must admit that the system works well.

And how about those “volunteer” plants that sprout in our gardens almost every year?  We never buried those seeds.  Many of us gardeners also self-seed herbs every year by keeping a few plants in the ground after harvest.

The point is that tearing up the ground every spring isn’t necessary for healthy gardens. Sowing seeds without tilling only causes a slight disturbance to the soil surface.

So, if tilling isn’t necessary, why are we doing it?

Some of you may have heard this story before, but it illustrates an essential part of our human nature:

A little girl was watching her mother prepare the Christmas ham and looked a bit puzzled.  “Mommy, why do you cut the ham in half before you cook it?”  Mom replied, “That’s how your Grandma taught me, but she never told me why.  Let’s call and ask her.”

So they called Grandma, and she said, “That’s how my mother taught me, so it must be the right way to do it.”  “But WHY do we do it?”  “I don’t know, you’ll have to ask her.”

Off they go, punching the numbers to call Great Grandma, hoping to get to the bottom of this mystery.  “Grandma, why do we cut the ham in half before we cook it?”  “Well, I don’t know why you youngsters do it, but I never had a pan big enough to cook a whole ham!”

Yes, it’s definitely in our nature to do things because “that’s the way we always did it,” without knowing the reasons why.  Our habits have inertia.  And that inertia keeps our habits moving in one direction until acted upon by an outside force.

In the case of our habits, that outside force ends up being a new idea entering an open mind.

Why did tilling become so popular millennia ago?  The people knew seeds could sprout on the surface of the ground.  I have a theory about that.

Birds and other animals will eat seeds on the ground before they sprout.  I suspect that’s one major reason that led to tilling: hiding the seeds from animal raiders.

Some other ancient reasons would include breaking up weeds and mixing in fertilizers.

What are the reasons for tilling?

There’s one good reason to till for a year or more.  That’s when there is dead soil or soil with heavy clay.

Those soil types need mixing with compost, wood chips, and other good organic matter.  Tilling is the best way to get the organics into the soil.

After enough treatment, the soil will have life in it.  The extra organic matter will also improve drainage and aeration.  Once the soil is fertile, there isn’t much reason to continue tilling.

Comparing till and no-till gardening

The claimed benefits of tilling

Here are the benefits claimed for tilling and the reasons why they’re not benefits:

Claimed Benefits of Tilling	Why it Isn’t a Benefit
It aerates the soil.	Organic matter and earthworm activity aerates healthy soil. Tilling disturbs the entire soil biome and harms the soil structure.
It breaks up the soil.	Yes, tilling loosens the soil at first.  Then it ends up compacting the soil. The whole process increases the rate of erosion.
Tilling facilitates drainage.	Tilled soil dries out faster.  Adding organic matter to the soil is the best way to improve drainage.
Mixes fertilizers with the soil.	The most fertile part of the soil is near the surface; the fertility doesn’t go deep.  Nature fertilizes soil from the surface.  Tilled soil loses nutrients faster, so it requires more fertilizer. Tilling often uses cover crops to increase soil fertility. This results in a cycle of building up the soil and breaking it down again.
Uproots weeds.	Tilling might break up weeds, but it also encourages the growth of buried weed seeds. Six of one, half a dozen of the other.

The benefits of no-till gardening

Benefit of No-Till Gardening	Explanation
Reduces moisture loss caused by turning the soil.	Turning the soil increases the exposed surface area, resulting in faster moisture evaporation. A thick layer of sheet mulching is a key part of no-till gardens. This is excellent protection against moisture loss.
Less soil erosion.	Maintaining the soil structure minimizes soil erosion.  Broken-up soil is easier to erode by wind and water.
Doesn’t disturb the soil biome.	Earthworm burrows remain intact so they can do their miraculous work.  Root systems, beneficial fungi and nematodes, and other healthy soil factors remain intact to do their good work.
Constantly builds up the soil.	It doesn’t break up the soil but builds up more good soil on top of good soil. Every growing season adds more healthy soil.
Requires less fuel and equipment.	One machine can scratch the soil and sow the seeds in commercial no-till farming. One pass and done.  Tilling requires plowing, discing, other soil prep, and sowing: more steps, more equipment, and more fuel.
Dormant weed seeds remain buried.	Many weed seeds start germinating when exposed to sunlight.  This is one reason why tilling causes more weed growth, and no-tilling reduces weeds. Another factor is the layer of cardboard or newspaper that’s spread on the ground before making a no-till bed.

Why leaving the soil structure intact is so important

Many benefits of not tilling center on the fact that it doesn’t disturb the soil structure.

Earthworms

These are remarkable little engineers.  The problem is that their job gets more difficult with tilled soil.  Tilling the soil destroys all the work they do to improve the soil:

• Earthworms eat fresh or decaying organic matter.  Their excrement (castings) is more nutritious for plants than the original organic material!
• Their tunnels aerate the soil.  They’re like a natural air conditioner.
• Besides aerating the soil, their tunnels allow water to saturate the soil better.
• The tunnels also make it easier for plant roots to penetrate the soil.
• With no-till gardening, earthworms enter the compost on the surface.  Then, they carry those nutrients into the soil.

Over the years, earthworms keep the soil fertile.  They also maintain the best conditions for growing plants.  Tilling the soil is like setting off a nuclear bomb.

It destroys the earthworms and everything they created.  The result is the soil is in worse condition.

When earthworms are in the soil, it’s a key sign that the soil is healthy.  See our article “Testing Garden Soil and How to Make Improvements” for more information.

The earthworms aren’t the only things to suffer.  Here are some other problems caused by disturbing the soil structure:

Mycorrhizal Fungi

These fungi create complex networks in the soil,  and have a symbiotic relationship with plants.  The word “symbiotic” means the plants and fungi help each other.

In this case, the fungi enter the plant roots and help the roots absorb water and minerals.  Tilling destroys the fungal networks, so they must regrow before helping any plants.

Upsetting the balance of beneficial organisms

Research at Washington State University shows that tilling reduces the aggregates in soil.  That decreases the habitat and food for beneficial organisms.

Tilling also changes the soil temperature and moisture.  That could increase some organisms and decrease others.  The result is soil that’s out of balance.

Conclusion

Based on the above evidence, we could say that tilling the soil upsets the soil conditions.  That makes the soil less beneficial for plant growth.  It could also lead to chemical (non-organic) methods to right the wrongs caused by tilling.

The best solution is to keep the soil undisturbed as much as possible.  That means less work for us gardeners and a healthier life for our plants. Give your herb or vegetable garden the conditions that make it thrive by using no-till gardening.

Continue the journey with our article “No-Till Gardening Methods: Discover the Expert Ways for Success.”