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Organic Gardening

Get dirty, have fun and grow more food with great gardening tips from real-life gardeners.


Gardening Is Biology not Chemistry

Go into the gardening department of any box store and you’ll find rows and rows of chemicals: fertilizers, herbicides, pesticides, fungicides. How did we get to thinking that growing food was a chemical process? Gardening professionals will tell you how much nitrogen, phosphorous, potassium, and other minerals such as boron, calcium, and magnesium, to add to your gardens. They’ll recommend adding lime to neutralize the acidity in soil. The list of chemicals experts suggest adding will empty your wallet. It makes you wonder how plants managed to survive before humans came along. Somehow they managed to make it to the modern era without the aid of humans.

Plants with roots appeared in the evolutionary record more than 400 millions years ago during the Devonian period. It’s only during the last 300 years that humans began developing mineral supplements and fertilizers. The process for creating nitrogen by fixing atmospheric nitrogen is barely a 100 years old. For over 400 million years, plants did splendidly without our help. The length of time plants have “required” human intervention isn’t even a blip of time. There are 86,400 seconds in a day, 31,536,000 in a year. The number of years humans have been spreading large quantities of chemicals on their fields and gardens is around a hundred years. Compared to the number of years plants with roots have been around, over 400,000,000, it is like 8 seconds out of an entire year. Insignificant. Nada. Zip.

When pioneers moved into the grasslands of the Great Plains, they discovered grasses ten feet and taller, growing profusely in arid conditions to boot. These grasses had been growing for eons, without the aid of any human fertilizers or minerals.

The most productive ecosystems on this planet, are the great rain forests along the Pacific Northwest Coast. These forests produce more biomass per acre than anywhere on earth. And they do this year after year, century after century, millennia after millennia, all without the assistance of our chemicals. From what gardening experts tell you, you would think that producing so much vegetation would quickly deplete the soil and strip it of all nutrients. Yet it never happens. The plants growing in the forest never run out of nutrients. Neither did the grasses of the Great Plains. And they fed vast herds of Bison for eons.

If these productive ecosystems can flourish for thousands of years without ever needing a drop of fertilizer, a teaspoon of pesticide, a sprinkling of herbicide, a spritz of fungicide, why can’t our gardens produce endless baskets of leafy greens, pecks of beans, and bushels of corn without chemicals? Have you ever stopped to consider that? Do our gardens and fields really need any of the bewildering array of chemicals the experts push, the box stores sell, and the chemical industry produces?

The mistake we made was treating food production as a chemical process instead of a biological process. I recently ran across a 90 minute presentation on YouTube by Dr. Elaine Ingham, Soil Microbiologist and founder of Soil Foodweb, Inc. The presentation was titled The Roots of Your Profits, and it was an eye opener.

In the presentation, Dr. Ingham explains how the sand, silt, clay, pebbles and rocks in your soil have all the minerals your plants will ever need for as long as you live and then way beyond that. There is so much nitrogen, phosphorus, potassium, calcium, and other minerals in your ground that your plants will never run out of them.

If you take a sample of your soil to a soil lab for testing, you’ll get a report back telling you how many macro nutrients like phosphorus and potassium, and how many micro nutrients like boron and manganese are in your soil. The report may also instruct you to add so much nitrogen, or limestone, or phosphorous, or something else. However, the lab is only measuring the soluble forms of these nutrients. In other words, the nutrient forms plants can absorb. What the reports don’t tell you is that these nutrients are in your soil in vast quantities in forms your plants can’t absorb. The thinking is that your plants have no way of using these insoluble forms. And yet they do. They know how to get to the inexhaustible store of nutrients in the ground. And how they do this is through a biological process that is as ingenious as it is amazing, and it’s a process plants have been refining for hundreds of millions of years. Through trial and error over hundreds of millions of generations, plants have become geniuses at feeding themselves.

What Dr. Elaine Ingham and other microbiologists have discovered is that plants enlist bacteria and fungi to get the nutrients they need. Plants do this by converting sunlight into thousands of varieties of sugars. Many of these sugars, they exude out their roots to feed the right mix of bacteria and fungi which will extract nutrients from the sand, silt, and clay particles in the soil. Along come organisms which feed on these bacteria and fungi, and the organisms leave behind nutrients in their wastes at the roots of plants which the plants slurp up.

Another good lecture to view, is Jeff Lowenfel’s Soil Food Web Lecture.

What plants need, is not for us to try and feed them with bags of various fertilizers and minerals. What plants need from us, is an environment where they can nourish the rich biology which will sustain them. The meddling we do by tilling, adding minerals and fertilizers, applying herbicides and pesticides, destroys the biology in the soil the plants need. As Dr. Elaine Ingham says, we have no idea minute by minute, hour by hour, what nutrients or how much water our plants need. But the plants know, and they know how to get them. Our role as gardeners is to  help them cultivate the biology they need, and in the process have healthy gardens and fields free of the fertilizers, herbicides, fungicides, and pesticides which do so much harm. A man and his hoe.


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