When working the land to grow food and energy crops our first priority and greatest resource is the soil. It has been said if humans take care of the soil then the sun and water will care for the plants. At the Willits Energy Farm we are developing a mini-farm template that factors in crop rotation systems, bed preparation, and a multi-faceted compost center designed to preserve and grow soil. As is evident by the abundance of earthworms that fill almost every scoop of soil, the site at Brookside Elementary has a nutrient rich soil high in organic matter. A soil analysis from December 2005 indicates that the percentage organic matter is 6% and there exists large reserves of exchangeable nutrients.

The same report shows that the soil is rich in microbial life including fungi, protozoa, and especially bacteria. Micro organisms are important aspect of the soil because they participate in the process of nutrient cycling and nutrient retention. Nutrient cycling is the conversion of organic matter and the exchangeable nutrients within the soil into plant available “foods”. Cycling occurs when bacteria and fungi decompose and metabolize organic matter in the soil. These microbes store the nutrients in their bodies (retention) and are themselves eaten in the processes and interactions within the natural food web of the soil. When a diverse set of microbes are interacting in the soil the nutrients are less susceptible to leeching out and the fungal threads and bacterial glues help form soil aggregates that resist compaction. As you might expect, healthy compost is a primary inoculum soil based micro organisms.

Given what has been said about the value of healthy soil, we have begun to plant out and seed spring annuals. These vegetables are transplanted in closely spaced sets and seeded densely in order to grow the greatest amount of food in the smallest space possible. On marginal soil this sort of approach may not produce desired yields as the plants struggle to find the nutrients in land that has been depleted or lacks the nutrient cycling provided by diverse microbial life. Although we have excellent soil to begin this project with we need to be careful not to deplete the reserves that have been stored up through the years. The Grow Biointensive method that we are pattering some of our crop spacing after admits that in order to produce large crops yields in a small space you will need to replenish the land and soil to make up for the nutrients used in the processes of growth. It is clear that we will need to amend the soil with compost after each section of annuals is finished.

Example of Intensive Planting of Onions and Lettuce

Intensive Planting of Peas, Beets, Cabbage, and Swiss Chard