What is in Black Dirt?

Black dirt is the term used to describe rich dark soil that is usually the result of rotted manure or compost. It may be marketed with a label of black dirt, manure or topsoil or any variety of names that refer to the particular animal the manure was derived from. As a garden additive, black dirt provides nutrients and builds the texture of the soil, improving water retention, aeration and drainage.

Types

Black dirt may occur naturally in undisturbed locations, such as under trees in a wooded area, where dead material is continually decomposing and adding organic matter to the existing soil. Soil that is left fallow for a year, or that has grown a cover crop, can be plowed to incorporate the organic matter into the soil. The process will enrich the soil and create black dirt if a regular schedule is followed and the soil is not overused for crop production. Compost bins that have new organic matter added regularly and are monitored for temperature, moisture and aeration will produce black dirt within a growing season. Manure piles that have ample amounts of straw or bedding materials mixed with the manure will rot and create black dirt.

Features

Black dirt contains organic plant material that has been broken down into small particles. These bits of organic matter improve the texture of the soil allowing it to retain water and provide ample air circulation needed for root growth. The soil is nutrient rich as the microbes have broken the plant matter down into usable units. Some bacteria draw nitrogen from the air and add it to the soil making it available for plants.

Function

Black dirt enriches the soil's texture by breaking up clay soils allowing water to drain and by adding water retention properties to sandy soils. The bits of organic material create air pockets in the soil that increase air circulation needed for strong root formation. It provides optimum conditions for the survival of beneficial insects and burrowing worms that also work to provide aeration and prevent the soil from becoming compacted.

Benefits

The increased nutrient content and the improved texture of the soil encourages healthy root growth which decrease the risk of run off and erosion. It reduces the need for fertilizer and pesticides. Black dirt is filled with micro-organisms that work to improve the health of plants and make them more resistant to pests and disease. It increases the water holding capacity of the soil reducing the need for watering during dry seasons.

Potential

Adding black dirt to a garden on a regular basis increases crop production and reduces the amount of time required to care for the plants. Food production, without the addition of chemical fertilizer or pesticides, results in an abundant crop without the health risks associated with consumption of foods with chemical additives.

Resources

• Composting Info