Why does soil matter for organic farming? We thought our readers and CSA Members would like to know why we don’t use hydroponics at our farm, and why we don’t support hydroponic production under the USDA National Organic Program standards.
This letter was written by Dave Chapman on the COMFOOD discussion forum, and explains it very well. Please note the letter was edited slightly for length, and links have been added by Amy Van Scoik at Frog Song Organics.
Four years ago, I got involved in the issue of hydroponics being certified as organic by the USDA (contrary to the recommendation of the NOSB and most world standards). I encountered people who genuinely asked, “Why does the soil matter?” What an important question! I had spent most of my adult life as an organic farmer believing in the importance of healthy soil. I had also spent much of that time in dialogue with large scale conventional hydroponic growers with a very different understanding of how to grow crops. We shared a deep curiosity about the most favorable climate for tomatoes in a greenhouse. My hydroponic friends smiled and shook their heads over how I grew, affectionately referring to me as a “dirt farmer.”
The vast majority of organic farmers believe that “organic” is deeply rooted in healthy soil. This is not a controversial idea in the organic community. In the work of the early thinkers such as Albert Howard, the conversation was much more about soil health than about pesticides. Why? Because the basic notion of organic agriculture is that a healthy soil can produce food that is healthier for people and other animals than that grown in “conventional” agriculture. The belief is that if you can get the soil right, then there will be much less pressure from insects and disease, which operate much like wolves thinning the caribou herd of the weakest. The foundational importance of healthy soil is true for livestock farming as well as for vegetables, fruits, and grains. There is a much greater reliance in organic farming on the soil food web, that amazing community of plants, microbes, and animals (both very large and very small) living above and below the surface of the soil. I have talked with a number of soil scientists during my work on the USDA Hydroponic Task Force, and those scientists believed, without fail, that there would be differences between food grown in a healthy soil and food grown hydroponically. But none of them were able to predict just what those differences would be. And as we have learned, we have only an incomplete understanding of what truly healthy nutrition might be. I am in the process of researching what studies are available on this subject. If any of you have information or contacts on this subject, please contact me.
What I have learned is that plants and soil have coevolved over 400,000,000 years. Our ancestors have been part of that coevolution for the past 6,000,000 years. In that unthinkably long time, our bodies have evolved to require a very subtle blend of some 33 nutrients (that we know of so far) in food. Some of these nutrients are required in homeopathic doses, while others are needed in much greater concentrations. Too much is as bad as too little. We depend on plants grown in an intelligent system. The plants rely on the fungi and bacteria in the soil to get those balances right. It has been said that the mycorrhizal fungi and bacteria are the “stomach” of the plant, making subtle decisions on how much of what nutrient a plant will need for optimal health. They then supply these nutrients in solution to the plant. In return, the plant supplies the microbes and soil animals with energy derived from photosynthesis. About a third of photosynthates are exuded by the plant roots to feed the microbes living around the roots.
This is basic soil microbiology and zoology. It is also the basis of organic farming. But one very significant ramification that I was unaware of until recently is the effect of a healthy soil carbon sponge on the climate. Not just due to carbon sequestration, which is important, but also due to the profound effect that a healthy soil has on the water cycle of the planet. Hydroponics have been touted as the answer to our growing water crisis, but hydro is only a band-aid on a serious problem. The real question is why do we have a water crisis in the first place? Why is California turning into a desert? I have heard compelling evidence that our broken system of agriculture has a great deal to do with that change. What is hopeful is that a reformed agriculture could also lead the way to the rehydration of California, and even to the cooling of our planet. This has been called the Brown Revolution, based on the reliance on “farming for soil carbon”. In this model, all farmers become carbon farmers. It is the answer to the failures of the Green Revolution, which is leading to a hotter and drier world that is much less green.
And so it is my thought that organic farming is more essential than ever. And not the USDA “new, improved, ‘sort of’ organic” but rather real organic, as envisioned by Howard, Balfour, and Rodale. The science of the last 60 years only supports the vision of those early pioneers. As it turns out, the more we learn, the simpler is the answer. Support real organic farming.
Long Wind Farm