what is compost? - Brief Article

Flower & Garden Magazine, Sept, 2001 by Wayne J. Mclaurin

ANSWERS TO COMMON QUESTIONS ABOUT COMPOST.

Question. Is compost a peat?

Answer. No. Peat is harvested from bogs and dried. It's formed over long periods by the decomposition of plant materials. Peat is a nonrenewable, limited resource, used mainly by the nursery industry as a soiliess potting medium.

Mature compost can be used in place of peat. It gives plants increased nutrients, makes water more available and reduces disease pressures.

Q. Is compost a mulch?

A. No and Yes. Mulch can be either an inorganic or organic ground cover. It can be pebbles, straw, shredded paper, bark, wood chips, plastic--any material that helps retain moisture.

Mature compost can be used as a high-quality mulch, especially around new transplants. Its slow release of nutrients to the soil gives transplants more protection from soil moisture and temperature fluctuations. And it makes water more available near the roots.

Q. Is compost a soil?

A. No. Soil is the uppermost layer of the earth. Soils are composed of various proportions of sand, silt, clay and small amounts of organic matter.

Mature compost is a complex organic material that has been transformed into stable humus by microorganisms.

Q. Is compost a chemical fertilizer?

A. No. Chemical fertilizers are inorganic compounds, composed of specific proportions of nitrogen, phosphorus and potassium (and sometimes other nutrients), that are soluble and readily available to the plant. Commercial fertilizer contains no organic matter.

Mature compost is, in part, an organic mixture of plant nutrients. These nutrients are released slowly, at a rate compatible with plant roots' uptake.

Q. Is compost a manure?

A. No. Manure is animal waste. It's often mixed with bedding or sludge and contains nutrients, weed seeds and potential disease organisms. Raw or partially processed manure isn't stable. It can release nutrients at less predictable rates than compost.

Mature compost can be produced from manure feedstocks and combined with bedding, leaves, chips or other carbon bulking agents. Proper composting, though, destroys weed seeds and potential disease organisms.

Q. Then what is compost? And howls it made?

A. Mature compost is stable humus material created by combining organic wastes (yard trimmings, food wastes, manures, etc.) in proper ratios into piles, rows or vessels; controlling temperature, moisture and oxygen to accelerate decomposition; adding bulking agents, such as wood chips, as necessary, to provide air space; and allowing the finished material to fully stabilize and mature through a curing period.

Decomposition happens when microorganisms such as bacteria and fungi use the organic materials for their food and energy sources.

Proper primary composting involves temperatures between 110 and 150 [degrees] Fahrenheit, moisture between 50 percent and 60 percent and adequate oxygen for the microbes. It's complete when the pile cools and remains below about 105 [degrees].

A subsequent curing period of two to six months is required for the compost to mature. After that, it won't overheat or produce unpleasant odors during storage. At that point, it becomes a true friend.

Q. Whose friend is compost?

A. Mature compost is the farmer's, gardener's, homeowner's, landscaper's and nursery operator's best friend. Compost provides many benefits as a soil amendment, potting mix supplement and mulch.

Q. What are specific benefits of compost?

A. Mature compost has many benefits to soils and plants. Among them, it:

* Improves soil structure.

* Increases the soil's nutrient-holding capacity.

* Reduces soil compaction and crusting.

* Lowers fertilizer requirements.

* Makes cultivation easier.

* Improves root growth and increases yields.

* Allows water to infiltrate better, making plants more drought-tolerant.

* Protects plants from disease.

* Increases microbial and earthworm populations.

* It also helps prevent and remediate pollution in a number of ways.

* Prevents erosion of embankments, roadsides and hillsides.

* Absorbs odors and helps degrade volatile organic compounds.

* Diverts organics from landfills, reducing waste and methane production.

For more information on composting and composting products, contact Mantis at 800.366.6268 and/or ComposTumbler at 800.880.2345.