Tuesday, September 28, 2010

Yet Another essay on Soil

The more I experiment with my gardens, the more I learn how connected we humans are to the Earth. Specifically for this talk is our obvious link to that very thin layer covering the rocky innards of our planet. If the Earth were the size of a beach ball, the layer of soil would resemble a generous layer of paint. So thin, so fragile, and if we are not mindful - so temporary.

It is late September 2010 and my composting program has reached maturity. I have added rich composted material to my gardens for three years running and the results are astounding. Despite the harsh San Antonio climate, I am able to pull ample fruits and veggies from my modest area of land. This year saw our very first peach crop. From a single mature tree and one young tree I put down last fall, we were endowed with several bushels of the tastiest yellow and white peaches one could imagine. Talk about guilt-free eating; completely organic! Tomatoes, onions, beans, peas, and peppers were their usual bumper quantities and this year we added Asian eggplant to the menu.

Now back to the soil. Something I have learned since my last post. STOP TILLING YOUR SOIL TO DEATH!! I will be the first to admit that I was guilty as anyone of over-tilling - always have been. I absolutely excelled at mixing my compost and literally pureeing my plots to ensure aeration, drainage, and all of the customary (and illusionary) benefits of "working" the soil. The truth is; healthy soil will take care of itself. Tilled soil isn't really soil - it's dirt. 40% of the nitrogen resident in soil is wrapped up in the bacteria living there. When you till, many of the bacteria are killed, releasing the nitrogen into the soil. Yes, this gives the plants a short-term 'boost' but that is quickly consumed and until the soil can reestablish itself, the plants have to look elsewhere or deeper for the necessary nitrogen and other nutrients (unless you try to add them via fertilizer). How does this work? Well it seems there are really only two types of roots - Tap roots and feeder roots. The tap root is the larger, main shaft that simply hydrates the plant - it takes in water. The feeder roots on the other hand are responsible for the feeding, the intake of nutrients the plant needs in order to grow and produce. These feeder roots are the small hair-like roots that spread out. At any rate, there is an exchange these smaller roots perform with the bacteria and various organisms in the soil. Without going into the painful details, the plant produces things that the organisms in the soil need and in return, those organisms produce things that the plant needs. Pretty neat huh? When you till the earth, you upset this whole economy and until it gets re-established, the plants and the soil are the worse for it. Stop tilling your soil.

SO - this year I put this into practice. Instead of working the new compost into the soil I only scraped back the mulch layer and added the compost over the top of the undisturbed soil. I have just planted my fall greens into the compost layer with the idea that the new plants will germinate in the rich compost and then reach down into and take hold of actual established soil, meanwhile the compost layer will continue to leech nutrients downward underneath the layer of mulch. Ironically, established soil retains moisture and resists erosion better than the powdery dirt we are conditioned to desire.

So, park the garden tiller and pick up a hoe.

Stay tuned over the next few months and I will let you know how this works out. Until next time - remain a part of nature...Kammy

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