8/4/14

Dirty, Filthy Gardening

"Dirt" -- also known as "Soil"
Dirt has an unfortunate pejorative association.  “Nostalgia for the mud” invariably means someone is dirty, filthy, smutty, low, base, and generally unwelcome at the kinds of parties one would not be embarrassed for one’s grandmother to know one is attending.  A baby who has soiled herself is an unwelcome dining companion; dirty dishes require immediate amelioration, and a dirty joke in the workplace will land you in hot water.

We would like to rehabilitate the concept of dirt, because, when it comes right down to it, a quality life depends on quality dirt.
Anyone who has ever attempted to grow any plant of any description has acquired at least a minimal appreciation for the idea that soil makes a difference.  Not all plants grow in the same kind of soil, and not all soil of the same kind is as nurturing of the same kind of plants, owing to a wide array of variables affecting “soil health”.

In general, soil health describes not the status of the soil, but rather its ability to convey the following benefits on organisms dependent upon the soil for nutrition and safety.  It can be measured by measuring the effect of soil conditions on:
  • Sustaining plant and animal productivity and diversity
  • Maintaining or enhancing water and air quality (themselves qualities measured in terms of their impact on their respective biological dependents)
  • Supporting human health and habitation

 Naturally, what is meant by “healthy soil” will depend upon what kinds of plant and animal life are dependent upon it – a healthy soil for the Amazon basin would be completely different from a healthy soil for the Alaskan tundra, or for a backyard garden in Tuscaloosa.  For that matter, a backyard garden in Tuscaloosa will have different requirements from a backyard garden in Tucson, or in Timbuktu.  You don’t grow the same kinds of plants in those three places, so you don’t need the same soil.

Therein lies one of the principal problems associated with the solutions to soil health presented by modern humans, in our ham-handed attempts to control nature... but we’ll get to that in a moment; we have some more expository ruminations to share before we get into the “Do’s” and “Don’ts”  of soil treatment.

One of the principal characteristics of soil which is most often ignored by those thinking about how to get more out of it is the concept that soil is its own little ecosphere.  An entire community of little critters move in and about particulate soil, feasting on a host of small plants, microbes, rhizomes, fungii, etc. that we never see nor think about.  The fact that we never think about this huge network of organisms, however, does not mean they are not important.  Quite the contrary.

We all know that one of the essential nutrients garden plants require is nitrogen – chemical-happy gardeners apply various fertilizers with a range of nitrogen contents in a frenzied attempt to monitor nitrogen levels in the soil... and even organic gardeners make valiant attempts to properly manage nitrogen levels through the use of correctly proportioned composted materials, and rotation of crops with nitrogen affixing qualities (mostly legumes).  We clearly approve much more strongly of the organic approach, of course, but even there, we would hope for a deeper understanding of natural soil chemistry than is usually present.

Basically, we’d prefer that people stop and ask themselves... how would these plants I am attempting to grow survive in the wild?  Humans didn’t always exist in order to intervene for these plants... so how did they get here?  What makes it possible for them to grow in the wild, but not possible for them to grow in my
backyard without me doing something?

These questions get to the heart of the matter.  The reason intervention is necessary in order to add nutrients to the soil (and nitrogen is just one of many)  is because intervention took away the natural means of those ingredients being present in the soil.

There are several mechanisms at work which have brought us to this state; the following is just a small sampling of the plethora of problematic human interruptions of healthy soil:
  • Suburban development has replaced natural layers with construction slag, and overlayed shallow grass sod on poor topsoils
  • Tillage (whether by rototiller or by shovel) has broken up long rhizomal connections between fungal and other microorganisms, eliminating the natural means for soil to compost itself
  • That same tillage has interrupted the food chain for creatures like earthworms who survive by consuming organic matter in this connected microscopic forest, so instead of a healthy hummus the soil turns into compacted clay
  • Watering of lawns laced with chemical fertilizers, herbicides and pesticides has killed of many of the microbial organisms who naturally aerate the soil
  • Watering from treated municipal sources adds salty deposits and chemical compounds not naturally found in topsoil (chlorine, fluoride, etc.)  Over time these compounds poison the microbial life necessary for healthy soil biochemistry

"Leaves" also known as "Fertilizer"
There is a reason fertilizer companies make so much money.  It is because the use of fertilizers (especially on lawns, which we have already indicated we really, really, really do not like) creates a perpetual cycle of malnutrition.  The more chemical fertilizer you add to the soil, the less healthy the microorganisms in the soil will become, and so the less fertile the soil will naturally be, meaning that in order to continue growing grass on that soil, more fertilizer will have to be added.

It’s time for that madness to stop.  Our addiction to lawns and to fertilizer are the fastest way we can think of to turn our suburban homescapes into vast, unhealthy desert badlands.
The same is true in large-scale agriculture, of course.  The Dust Bowl was essentially the result of depleted topsoils caused by overproduction, where the natural layers of microbial life no longer had enough nutrition to form a matted, connected whole.  There is a misconception that plants hold the soil together, preventing topsoil from blowing away.  It’s not the visible organisms that keep the soil in place, it is the organisms you don’t see, much like the seams in a shirt, which keep the good dirt where it is supposed to be.

There is a better way.  Even some of the most egregious monocropped agribusinesses go part of the way towards the light – decreased tillage has become much more common in large scale farming, and you will frequently see fields where crops are left in situ after harvest, where the stalks are basically composted in place.

More can and should be done to improve commercial farming practices, of course, but for now we would like to focus on what the small-scale producer (such as a backyard gardener or market farmer) can do to rehabilitate our worn out soils.

For starters... the answer to those questions we were asking earlier, about how various plants might have survived in the wild prior to the invention of gardeners, holds the key to enlightenment:  soils in nature contain the nutrients necessary for plants in their respective ecological niches to grow for two very simple reasons:
  1.             The soil has naturally “cooked” according to local recipes, including fallen leaves, local water sources (whether rain, alluvial flooding, whatever), and the local variety of microflora and microfauna.
  2.       The plants growing in the given soil are native to that soil.


It really comes down to something very simple... all the testing your local agriculture extension agent suggests is superfluous – you don’t need to do it.  To verify that your soil is healthy, simply make sure that leaves, twigs, etc. that rot in nature in your area are rotting in your garden, too.  And when it comes time to plant something in your rotted soil... plant things that naturally grow in your area, or an area very much like your area.

"Raised Bed" also known as "Dow Chemical and Monsanto
Can Suck Chicken Poop Through a Straw"
Rather than rototilling vast plots, pouring large quantities of herbicide on the inevitable weedy invaders, and applying whatever fertilizer (chemical, organic, doesn’t matter – any fertilizer), a healthier approach is to heavily mulch whatever area you are wanting to cultivate, using natural local materials (we use oak leaves, of which the Brazos Valley provides a vast quantity), and wait for the inevitable rot to take its course.  If you keep a compost bin, that’s fine – we use mucked out chicken coop soil comprised of broken down leaves and chicken poop – but composting in place is just as good.
If you’re worried about weedy invaders, we recommend using raised plots, putting down cardboard or paper first to blot out the sun, and then covering with “stuff that rots”.  The rotting is very important, as is the “not tilling too much”.  There’s a vibrant network of filaments and roots that you just can’t see, comprised of little critters who are doing the hard work for you of making sure there are properly balanced amounts of nitrogen, calcium, etc. ad nauseum, so that your beans, squash, cucumbers, whatever, are perfectly happy in the soil bed you have helped fashion.
But what about soil depletion in future years, when whatever crops you’ve grown have depleted these beds of “rotted stuff”?  We’re glad you asked.  Once you’ve successfully grown things in a bed of natural soil... harvest your crop, and leave the plants in place to rot in their turn.  Add more leaves.  Treat your garden plot like a little corner of a natural forest.  That’s where squash, cucumbers, beans, etc. grew before there were people involved, right?  This ain’t rocket surgery, people.  A healthy person can thrive without a respirator or a dialysis machine.  Healthy soil is soil that can grow things without medical assistance.

Now then, anybody know any dirty jokes?

Happy farming!

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