Successful gardening depends on the health of your soil
As modern gardeners we typically enrich the soil with commercial fertilisers rather than composting; not only are these expensive substitutes for the real thing, they are also bad for the environment.
Composting as a recognised practice dates to at least the early Roman Empire where composting was simply to pile organic materials until the next planting season, at which time the materials would have decayed enough to be ready for use in the soil.
Composting is nature’s way of recycling by transforming organic matter that is ready for disposal into something beneficial.
Basically, organic materials like grass clippings, vegetable matter, egg shells, coffee grinds, tea bags (anything that is not animal-based) are placed in a suitable container or pile to decompose.
Over time, these materials turn into a rich form of soil, humus, the heart of the soil ecosystem.
In order to stay organic, be sure everything you compost is also free of toxic chemicals
By composting, you can help to reduce the amount of waste that is being directed into our landfills. This also means a reduction of concentrated methane gas being released into the atmosphere, which equates to a decrease in overall pollution. Less garbage being sent to the landfill also means a reduction in waste management costs for our community, and eventually for the entire country.
Composting also cuts down on the use of chemical fertilisers, which are harmful to our water supply, and are expensive to produce and transport.
Maturing Compost and Why it’s Important
Maturity is the degree or level of completeness of the composting process. For mature compost the starting materials have been sufficiently decomposed to produce a stable product. In contrast, immature compost that is still decomposing may contain one or more compounds that inhibit plant growth, may contain viable weed seeds, or have other undesirable characteristics, such as odor.
Composts vary quite widely in their chemical and physical characteristics, depending on the original materials used and the conditions maintained while the material was composting. In general, though, composts share the ability to provide these benefits:
- Plant available nutrients and micro nutrients and unlike most inorganic fertilisers, compost functions as a slow-release store of nutrients, so that the nutrients are available as the plants require them instead of in one intense flush.
- Organic matter which increases the soil’s water holding ability, allows better infiltration of both air and water and the soil structure is improved. Earthworm activity is also encouraged, further enhancing soil fertility.
- Biological activity. Compost is biologically active, supplying a range of microorganisms that enhance the health of both soil and crops.
Most compost are in the neutral pH range by the time they are mature, however this can depend on the materials used. Make sure you test the PH levels of your compost before adding to plants and adjust with lime or sulphur as necessary, at this time.
Methods of Composting
Basically there are two methods aerobic and anaerobic. The first of these methods uses air, for example by turning the materials which generates high heat and speeds up the process of decomposition. This is often referred to as the Berkeley method.
The Indore method is the second and relies on the build up of anaerobic bacteria to do the work of breaking down the organic matter. The heap can be either free standing or made in a compost bin and is the simplest way with the least effort.
Whichever method or container you use for making compost, you need to have a mixture of carbon rich and nitrogen rich materials as well as manure.
A relatively new method of intensive composting is Bokashi which is suitable for in home composting applications. Kitchen waste is placed into a container which can be sealed with an air tight lid. These scraps are then inoculated with a Bokashi Effective Microorganism mix. This usually takes the form of a carrier, such as wheat bran or saw dust that has been inoculated with composting micro-organisms. The EM are natural lactic acid bacteria, yeast, and phototrophic bacteria that act as a microbe community within the kitchen scraps, fermenting and accelerating breakdown of the organic matter.
To use this method simply place alternating layers of food scraps and Bokashi mix until the container is full. Liquid is drained once or twice a week and can be diluted 1:100 and added to plants as fertilizer. Once the container is full, it is left to ferment for an additional 2 weeks in the container, and then can be buried or added to your other compost heaps or containers.
The Future of Composting
Although the most efficient and environmentally friendly process is for individuals to compost their own waste, large-scale composting systems are used by many urban centres around the world reducing landfill and producing a rich soil supplement instead.
Co-composting is a technique which combines solid waste with de-watered bio-solids. Currently the world’s largest co-composter is the Edmonton Composting Facility in Canada, which turns 220,000 tonnes of residential solid waste and 22,500 dry tonnes of bio-solids per year into 80,000 tonnes of compost.
The State of Qatar is this year completing a project on a 275,000 tonne/year Anaerobic Digestion and Composting Plant. This plant, with 15 independent anaerobic digesters will be the world’s largest composting facility once fully operational in early 2011 and forms part of the Qatar Domestic Solid Waste Management Centre, the largest integrated waste management complex in the Middle East.