for: composting

Compost ( or US /ˈkɒmpoʊst/) also known as brown manure, is the aerobically decomposed remnants of organic matter. It is used in landscaping, horticulture and agriculture as a soil conditioner and fertiliser. It is also useful for erosion control, land and stream reclamation, wetland construction, and as landfill cover (see compost uses).

Compost serves as a growing medium,or a porous, absorbent material that holds moisture and soluble minerals, providing the support and nutrients in which most plants will flourish. To maximize plant growth, it is sometimes necessary to dilute compost with soil or peat to reduce salinity or to add neutralisers to bring the pH closer to 7, or additional nutrients like fertilisers or manure, wetting agents, and materials to improve drainage and aeration, such as sand, grit, bark chips, vermiculite, perlite, or clay granules.

Composting as an alternative to landfill

As concern about landfill space increases, worldwide interest in recycling by means of composting is growing, since composting is a widely accepted process for converting decomposable wastes of biological origin into stable, sanitized products useful for horticulture. The more recent application of composting for large-scale waste reduction has very little in common with organic farming. The 1999 European Landfill Directive put pressure on European states to meet specified targets for landfill reduction, principally by establishing alternate disposal and treatment of organic materials. While certain countries such as Belgium, Holland, Germany and Austria readily achieved the mandated targets, other countries such as the UK, Spain and Italy have not. Indeed, it is commonly accepted that the UK, despite its early important contributions to organic farming and John Innes Compost, started taking composting seriously only after Brussels threatened a penalty for states not attaining the required reduction targets. A recent National Audit Office report for England warned that councils were in danger of missing EU targets to cut the amount of waste at landfills. The NAO's report stated that to meet European targets for 2010, a reduction in the UK of at least 3.5m tonnes of biodegradable waste sent to landfill was needed. A reduction of a further 3.7m tonnes was needed by 2013. Less than one-half this has been currently met.

Modern large-scale composting should therefore not be confused with an idealistic, organic-oriented goal to recycle and improve soils; since, for most western countries now, it is virtually the law. These factors could lead to a conflict between required production of composts and the quality of the product.