Improving Soil Fertility

Healthy soil consists of a combination of minerals, water, air and organic matter. Worms and billions of microbes live in healthy soil, decomposing and converting soil components into useable plant nutrients.

Characteristics of Poor Soil

Poor soil contains little organic material, worm or microbial activity. Food plants grown in poor soil will be vulnerable to pests and diseases while weeds flourish. In order to bring poor soil back to health it is important to recognize that soil nutrition is key. The soil must be fed before it is able to feed the plants grown in it. Few nutrients in the soil means few nutrients in the food plants.

Chemical Fertilizers

Chemical fertilizers bypass the microbial source for plants to obtain their food, often killing beneficial bacteria and fungi. Microbial activity eventually ceases. With continued use, only regular additions of chemical fertilizers will then enable the soil to support plant life. At harvest, while dozens of minerals are removed from the soil only a few of them are replaced through chemical fertilization. Salts in chemical fertilizers can also be poisonous to earthworms.

Feeding the Soil

Various methods may be used to improve the fertility of soil. One of the most valuable is the addition of compost. Large quantities of finished compost may be added even at planting time without any risk of burning the delicate root systems of young plants.

Compost

To build a compost heap simply alternate thin layers of brown and green material. Brown material is older, dryer, plant ingredients like dried grass stems, old corn stalks, dried peas or old hay. Purchasing straw may be necessary to obtain sufficient brown material. Green material is made up of young, moist, fresh ingredients like kitchen wastes such as fruit and vegetable peelings, eggshells, coffee grounds and carrot tops or garden wastes such as fresh grass clippings, cabbage leaves or fresh pea vines. The New Brunswick Department of Environment offers an online composting handbook.

Well-rotted manure is another good organic soil amendment. The best manures to use are horse, cow, sheep and goat. These may be left to break down on their own or added to the compost pile.

Attracting Earthworms

The addition of compost will also attract earthworms to the soil. Worms eat organic matter and tunnel, helping to aerate and drain the soil. After predisgesting the material, worms excrete “castings”, leaving behind them fertile tunnels for microorganisms and the growth of plant roots. As well as having a large population of bacteria, worm castings are rich in nitrogen, magnesium and phosphorous. Combined with the air channels provided by tunnelling, the result is an almost perfect environment for plant growth.

Worm Composting

Worm composting assures a steady supply of nutrient-rich castings for either outdoor gardening or indoor gardening. Redworms are kept in a ventilated covered bin to which a bedding of soil or shredded newspaper is added. The worms eat kitchen scraps buried in the bedding, their favorites being coffee grounds and eggshells, and turn it into rich fertilizer.

The Chicken Tractor

If the patch of ground intended for a garden is thick with weeds, another interesting method of improving the soil is to use the chicken tractor. A small portable coop is placed atop an overgrown section and the chickens make short work of weeds and weed seeds, greens and insects before being moved along. They contribute manure and their scratching loosens the soil. Add a nesting box and the chickens will also supply fresh eggs!

Resource:

Four-Season Harvest by Eliot Coleman

Chelsea Green Publishing Company, 1999