Compost Fertilizer

Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost is a key ingredient in organic farming. At the simplest level, the process of composting simply requires making a heap of wetted organic matter (leaves, "green" food waste) and waiting for the materials to break down into humus after a period of weeks or months. Modern, methodical composting is a multi-step, closely monitored process with measured inputs of water, air, and carbon- and nitrogen-rich materials. The decomposition process is aided by shredding the plant matter, adding water and ensuring proper aeration by regularly turning the mixture. Worms and fungi further break up the material. Aerobic bacteria manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium. The ammonium is further converted by bacteria into plant-nourishing nitrites and nitrates through the process of nitrification.

Compost can be rich in nutrients. It is used in gardens, landscaping, horticulture, and agriculture. The compost itself is beneficial for the land in many ways, including as a soil conditioner, a fertilizer, addition of vital humus or acids, and as a natural pesticide for soil. In ecosystems, compost is useful for erosion control, land and stream reclamation, wetland construction, and as landfill cover (sees compost uses). Organic ingredients intended for composting can alternatively be used to generate biogas through anaerobic digestion

Ingredients

  • Carbon — for energy; the microbial oxidation of carbon produces the heat, if included at suggested levels. High carbon materials tend to be brown and dry.
  • Nitrogen — to grow and reproduce more organisms to oxidize the carbon High nitrogen materials tend to be green (or colorful, such as fruits and vegetables) and wet.
  • Oxygen — for oxidizing the carbon, the decomposition process.
  • Water — in the right amounts to maintain activity without causing anaerobic conditions.

Although the density of nutrients in organic material is comparatively modest, they have many advantages. The majority of nitrogen-supplying organic fertilizers contains insoluble nitrogen and act as a slow-release fertilizer. By their nature, organic fertilizers increase physical and biological nutrient storage mechanisms in soils, mitigating risks of over-fertilization. Organic fertilizer nutrient content, solubility, and nutrient release rates are typically much lower than mineral (inorganic) fertilizers.[12][13] A University of North Carolina study found that potential mineralizable nitrogen (PMN) in the soil was 182–285% higher in organic mulched systems than in the synthetics control Organic fertilizers also re-emphasize the role of humus and other organic components of soil, which are believed to play several important roles:

Advantages

  • Mobilizing existing soil nutrients, so that good growth is achieved with lower nutrient densities while wasting less.
  • Releasing nutrients at a slower, more consistent rate, helping to avoid a boom-and-bust pattern.
  • Helping to retain soil moisture, reducing the stress due to temporary moisture stress.
  • Improving the soil structure
  • Helping to prevent topsoil erosion (responsible for desertification and the Dust bowl.
Organic fertilizers also have the advantage of avoiding certain problems associated with the regular heavy use of artificial fertilizers:
  • The necessity of reapplying artificial fertilizers regularly (and perhaps in increasing quantities) to maintain fertility.
  • Extensive runoff of soluble nitrogen and phosphorus, leading to eutrophication of bodies of water (which causes fish kills)
  • Costs are lower for if fertilizer is locally available