In Praise of Compost
By Thaddeus Barsotti
In my early days of farming I went through a phase of harvesting crops and immediately planting new ones without amending the soil. The results were decreasing yields and declining crop health. It was a good lesson, and helped me understand that the true challenge of organic farming is to find a sustainable method for giving the ground what it needs to produce the crops that feed our people. What comes out of the ground in the form of fruits and vegetables ultimately must go back into the ground.
One of the most important elements required to grow healthy crops is nitrogen, so this is the basis of my farm’s fertility program. Organic farms are only permitted to apply materials that occur in nature; anything that has been chemically altered from its original form is not permitted. This rule eliminates synthetic nitrogen from use on organic farms, leaving compost, properly composted animal manures, products derived from ground fish or seaweed, and processed animal byproducts like chicken feathers as acceptable fertilizers. I don’t enjoy using the animal byproducts, and so I rely mostly on composted food scraps. This compost originates from your green waste, and compostable items from food-service industries. After several weeks of being properly composted, these items turn into a black mass of organic matter, nitrogen, and trace levels of all the essential elements needed to grow food. In general, compost like this is about 1.5 percent nitrogen by weight. In order for me to apply the 120 pounds per acre of nitrogen a typical crop requires, I must spread 8,000 pounds of compost per acre per year for each crop cycle. One semi truckload of this compost is about 40,000 pounds, enough for five acres of land. In contrast, synthesized urea is 47 percent nitrogen, and in order to feed my soil the same 120 pounds of nitrogen per acre, I would only need to apply 255 pounds of urea per acre per year.
This cuts down on the amount of fuel needed to transport the fertilizer from the source to the field, which might make urea sound like a better approach. But one must look at the big picture to see the benefits of compost. The first observation about synthetic fertilizers is that they are derived from fossil fuels, which are obviously not sustainable, and which require manufacturing. The next observation is that synthetic fertilizers are very specific and precise in what they are adding to the field. Compost, on the other hand, includes a larger array of the nutrients necessary to the health of plants. Compost is like a health-food shake for the soil. Another thing to consider is that compost is a byproduct of urban life. What better way to deal with waste than to compost it and apply it to a field, literally recycling the biological value of the material? Especially when the alternative is to put the product into landfills.
Compost is our soil’s health food and an important part of healing and connecting farming, cooking, and food waste. •
Thaddeus Barsotti is a second-generation organic farmer in the Capay Valley. He and his three brothers grow over 60 different fruit and vegetable varieties on their farm, Capay Organic, founded in 1976. Their Community Supported Agriculture (CSA) program, Farm Fresh To You, delivers fresh, organic produce directly to Bay Area doorsteps. To learn more, visit farmfreshtoyou.com or call the farm at 800.796.6009.