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Building Healthy Soil

When most people think about the difference between conventional farmers and organic farmers, they think of chemical pesticides. Ask an organic farmer about the cornerstone of organic farming, and their answer will always be "creating rich, healthy soil."

Proper preparation and stewardship of the soil is the foundation of organic farming — to a large degree, that's what makes it possible to grow crops without relying on the many chemicals used in conventional farming.

Developing healthy, fertile soil the organic way

Healthy soil, rich in organic matter, is "alive" with microorganisms. These vital organisms break down nutrients to make them available to plants, making the soil more fertile and helping control soil-based plant pathogens.

Every time crops are harvested or weeds pulled, nutrients and organic matter are withdrawn from the soil; if they're not replaced, the soil is eventually depleted of the very resources plants need to flourish. So organic farmers think about how plants will be nourished well in advance of planting time. We make sure our soil is rich in "organic matter," the part of the soil that is comprised of anything that once lived, including plants and soil organisms. Fields high in organic matter have less soil erosion, retain water better, and release nutrients more slowly into the soil for natural, healthy plant growth.

At Earthbound Farm, we build the fertility of our soil in a variety of ways:

  • Compost — We use quality organic compost, which recycles plant and sometimes animal waste materials into nature's best plant food, containing high-quality organic matter and beneficial microorganisms. Microorganisms (bacteria, fungi, nematodes, protozoa, earthworms) break down (digest) the raw components of compost, generating heat. The compost mixture reaches and maintains an internal temperature of 131 to 149 degrees Fahrenheit for at least 5 days to kill any disease-causing bacteria and weed seeds before it is used in a field. We also use pelletized chicken manure, which has been heat-steam processed to kill unwanted bacteria.

  • Cover crops — Whenever possible, we plant cover crops (such as Austrian field peas, bell beans, and vetch) and till them under. These cover crops replenish the soil with nutrients (such as nitrogen) and organic matter.

  • Natural minerals — We sometimes add natural minerals to improve our soil's consistency and pH balance. For example, if we need to lower the pH (make the soil more acidic), we may add mined sulphur. To raise the pH (make the soil more alkaline), we may add powdered limestone. The best soil pH range for most vegetables is between 6.0 and 7.0.

  • Crop rotation — Planting one type of crop over and over in the same location ("monocropping") depletes the soil of nutrients needed by that crop; for example, corn depletes nitrogen. Rotating peas and beans with corn helps add nitrogen back into the soil.

The cost of using synthetic fertilizers

Conventional farmers rely on various chemical fertilizers to nourish their crops. These synthetic fertilizers provide more precise and immediate control over the growth rates of crops, but at a cost:

  • Synthetic fertilizers can pollute the environment when they're manufactured.

  • Synthetic fertilizers can leach into the water supply after they're applied.

  • Most synthetic fertilizers are made from petroleum, a non-renewable resource.

  • Most synthetic fertilizers require a lot of energy to produce.

Organic farming preserves natural resources by recycling and using renewable materials. At Earthbound Farm, most of the materials we use to increase soil fertility are recycled byproducts from other industries that might otherwise go to waste. A principal ingredient of Earthbound Farm's compost is plant parts left over after harvest. We may also use pelletized feather meal, pelletized chicken manure, fish slurry, and pelletized bat and seabird guano. This ingredient list may sound unappealing, but utilizing these waste products enables us to grow healthy plants without the use of petroleum-based fertilizers.

Slower-growing organic plants have a longer shelf life and lower nitrate levels

When it comes to the final product you buy in the grocery store, all the organic farmer's hard work really pays off. Plants fed with synthetic fertilizers can actually grow too fast, creating cellular material which is thinner than that of more slowly growing organic plants. This means that if both products are handled correctly, our organic salads actually have a longer shelf life than their conventional counterparts.

Organically produced foods have also demonstrated lower levels of pesticide residues and, in many cases, lower nitrate content. According to the UN Food and Agriculture Organization, "A number of studies show that when nitrates, a common element of artificial fertilizers, are converted to nitrosamines, they may be carcinogenic. The nitrate content of organically grown crops is significantly lower than conventionally grown products."

Next in Organic 101:
Controlling weeds without toxic chemical herbicides

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