Not all organic farming is sustainable, but all sustainable farming must be organic. As organic farming grows and more and more large operations sprout up, attempts to broaden the range of what may be included under the term organic have increased.
Just as the term organic is subject to change and interpretation, so is the term conventional. In my lifetime (60 years), its meaning has shifted from referring to what we would now call "organic" to referring to petrochemical- and toxic-dependent farming. In many parts of the world, it now assumes transgenic (GMO) crops.
Truly organic farming is an ecological approach that attempts, as much as possible, to "close the loop" of the energy, carbon, nitrogen, water, and micronutrient cycles. This is difficult; when you buy organic food, you are taking these valuable substances from the farm. The organic farmer ensures they are replaced, while minimizing use of non-renewable resources. Balance is achieved through inputs from the world's energy and water cycles, nitrogen-fixing crops, and waste products (e.g., manure).
Local food production goes hand-in-hand with organic farming to extend this principle of ecological balance "beyond the farm gate." It is more energy-intensive to eat foods from further away because of the energy used during transportation.
Ever since the dawn of agriculture about 10,000 years ago, human activity has been depleting the earth's soil. Organic farming attempts to rebuild soil by treating it as an organism rather than a medium. A good organic farmer feeds the soil, not the crops. Healthy soil is an incredibly diverse ecosystem. Fungi liberate formerly inaccessible minerals and form symbiotic relationships with photosynthesizing plants, exchanging minerals for sugars (energy). Bacteria do the difficult task of fixing the almost-inert but vital gas nitrogen, which is important in all our metabolic and reproductive systems. These functions can only occur if the soil is fostered, and not if it is poisoned.
If organic farming is so sustainable and doesn't require petrochemical inputs, why is organic food so expensive? The short answer is that it's not. For example, if I, as a physician, go to a pharmaceutical presentation at an expensive restaurant and am not given a bill, does that mean that the meal is free? Obviously not. The restaurant is paid by the pharmaceutical company, and ultimately, the drug consumer pays for my meal. "Conventional" farming relies on others, usually taxpayers, to pay much of the bill. As taxpayers, we all subsidize mineral exploration and then transportation in the form of roads and pipelines (for gas, the feedstock for nitrogen fertilizer, etc.), as well as cleanup of agricultural pollution, not to mention transportation-related air pollution. If the cost of cleaning up the Great Lakes of agricultural waste were added to the cost of Ontario beef, for example, the cost of a steak would be astronomical. Organic farmers do not ask you to help defray the cost of your food; they have already done it for you. You have paid the cost of inputs, as well as the cost of waste disposal, when you complete your organic food transaction.
Organic food is clearly healthier for the planet, but is it healthier for you as an individual? We are so diverse (what scientists refer to as "heterogeneous") that it is impossible to find a clear answer. We all swim in a planet-wide "soup" of man-made chemicals. Some of us try to minimize our exposure, and people who eat organic foods do have fewer pesticide residues in them. Organic foods also have generally been found to have fewer nitrites (bad things) and more of the good things, like antioxidants, in them.
Thomas Pawlick, in his book The End of Food, documents the decline in nutrient value of foods over the past few decades, as recorded by the U.S. Food and Drug Administration. Potatoes and tomatoes have far fewer nutrients than they once did, as they have been bred for shelf life, durability in handling, colour, and uniformity but not flavour or nutrient value. At an organic farm, you are likely to encounter heritage varieties grown as they were before this nutritional decline.
Organic growing is labour-intensive. Petrochemical agriculture was developed to minimize labour; it is more productive per unit of farmer's time, but not per unit of land area. We can grow enough food to feed the planet organically, but we will need more farmers. Another way of saying it is that organic farming invites participation, both from thoughtful eaters and workers and growers.
Art Wiebe, M.D., CCFP, FRRMS (Fellow in Rural and Remote Medicine), has been a rural physician for more than 30 years and is a board member of the Canadian Association of Physicians for the Environment. He lives on 44 hectares of land on the shore of Lake Huron, where he and his wife, Janice McKean, have a small ecological farm, selling at a local farmers' market. They study, grow, and sell indigenous plants, run a farm Bed & Breakfast, and enjoy the company of their national heritage-breed horses, the Canadien. (His garlic won first place at both the Tiverton and Kincardine Fall Fairs in 2009.)