Manure in the Organic Garden

The excrement of any vegetarian livestock can be a potential source of organic soil enrichment for the home gardener. Besides being a natural source of fertilizer that farmers and gardeners have used for millennia, manure enriches the soil by improving its tilth and humus content.

Manure Types

The most common manure types used in the organic garden include cow manure and horse manure. Sheep manure is also a valuable addition to the compost pile, as it is particularly rich in potash. As a rule, the manure from grain fed animals is higher in nutrients that that from grass fed animals. Poultry manure is the richest of all, so gardeners must compost it completely to avoid the risk of burning tender plants.

Gardeners must never use the manure of carnivorous pets, such as dogs or cats, although rabbit litter is fine in the garden. Carnivorous pets can carry parasites that may pass to humans through the soil. Dispose of pet feces properly, and don’t allow pets to relieve themselves in the garden.

Composting Manure

Adding manure to the compost bin can heat up even the coldest of piles. The ideal way to compost manure is by mixing it with the animal’s typical bedding, which may be straw or hay. This provides the ideal blend of nitrogen and carbon that yields high quality compost. The resulting compost will not have the strong odor fresh manure has. If no bedding source is available, add chopped brown leaves as a carbon source.

Fresh Manure

Although farmers commonly apply fresh manure to fields using manure spreaders, this results in lost nutrients through the escape of gases and the leaching of nutrients via rainwater. If the manure is applied fresh, the farmer or gardener must work it into the soil immediately so the nitrogen will remain in the soil.

Fresh manure never has a place in an actively growing garden. The high nitrogen content can burn the leaves and roots of growing plants. Gardeners may only apply fresh manure in the fall, allowing time for decomposition in the winter months.

Manure Sources

A single horse or cow can produce between 18,000 to 27,000 pounds of manure each year, so the organic gardener with a farming friend need look no further for a manure source. Bagged manure from livestock is common at home and garden centers, but the gardener has no way of assuring the organic status of these products.

Gardeners living close to a zoo may inquire about the availability of manure from exotic vegetarians, such as elephants or rhinoceroses. Some zoos even package this manure and have an annual sale to raise funds for the facility.

Manure Tea

Gardeners in need of a quick source of liquid fertilizer can make manure tea from composted manure. Fill an old towel, rag, or pillowcase with a shovelful of manure, and tie the cloth shut with twine. Soak the manure in a bucket of water overnight. Use the nutrient rich tea to water flowers, vegetables, container plants, and even houseplants.

Source:

Rodale, R. (1999). The Encyclopedia of Organic Gardening. Rodale Books, Inc: Emmaus, PA.

University of Wisconsin Department of Horticulture