Compost is a generic term used for organic matter that has decomposed and can be used to fertilise and aid the growth of plants.
Compost can be produced from everyday waste materials, such as garden weeds, egg shells and potato peel. In fact, it is estimated that 30% of household waste is compostable. It can also be mass manufactured to produce the best results and is used in almost all agricultural and horticultural endeavours to increase plant growth. It is dark brown and friable in appearance.
Common compost, ready to use. Image Credits: casperwy.gov
Peat is a naturally forming, organic substance which forms in anaerobic conditions (in the absence of oxygen) usually in the presence of stagnant water. It is usually formed in mild climates, such as those found in the northern hemisphere. It is an extremely fertile growing medium for various types of flora.
Peat is an integral part of modern gardening, due to its fertile properties and is often the main ingredient in modern, store-bought composts.
Used by both amateurs and professionals, peat-based composts came into common usage in the mid-20th century. It is often mixed together with sand and loam, though many commercial composts are almost 100% peat.
Natural, concentrated peat, the precursor of coal. Image Credits: usgs.gov
What are the benefits of using peat-based compost?
Peat has allowed the gardening industry to thrive, as it is perfect material for growing a wide variety of plants, from cucumbers to chrysanthemums. The natural nutrients in peat, present due to the partially decomposed plant material, make it the easiest medium to use to give gardens a kick-start. Hence, amateur gardeners are the biggest users of peat-based composts. It is also the only viable option for certain specialist plants.
Another reason why casual gardeners continue to buy peat-based composts is the price. Many peat-free composts require extra processing and hence the price goes up. It is also the case that if a gardener finds a compost that works for them, they will be reluctant to change to newer brands that have a reputation for being unreliable.
Many leading gardeners still use peat based composts to some extent.
What are the Potential Environmental Drawbacks to Peat-based Compost?
The peat that is used to produce the garden compost is mainly derived from peat bogs. Peat bogs are among the rarest and most fragile environments in the UK, and are often hundreds of years old. Natural peat bogs are being destroyed to meet the demand for composts and the peatlands of the UK have hence become some of the most endangered natural habitats in the country. With only 6000 hectares of bog left in the UK that is in a natural condition, this equates to a loss of 94% of all peatbogs in the UK.
The intensive mining of peat has adverse effects on the climate, and destroys valuable ecosystems. Many rare and endangered species live in and around peat bogs and these are having their way of life threatened. Species that live around the bogs include dunlins (a rare species of wader), dragonflies and butterworts (rare carnivorous flowers).
A peat bog in America, where conditions are perfect for peat formation. Image Credits: epa.gov
The peat business is also extremely damaging to the climate, as estimates believe that removing and processing peat for composts release around 630 000 tons of CO2 into the atmosphere. The peat used in the UK is also sourced from Ireland or Baltic nations such as Estonia, Latvia and Lithuania, meaning further carbon is emitted during transportation.
Though the problem with peat has been known for at least 20 years, it has been very difficult to phase out of common usage, with almost half of composts used in Britain continuing to be peat-based.
There was a campaign in the 1990’s to try and drastically reduce the amount of peat in compost and a complete phase-out of peat was hoped to have occurred by 2010. However, most professional gardeners admit that it is very hard to stop using peat altogether, because there does not seem to be a sustainable substitute with the same properties.
Famous gardeners that have spoken out against using peat-based composts include Alan Titchmarch, Monty Don and Charlie Dimmock.
Some conversation societies are petitioning to have peat-based composts banned all together from British gardens. The RSPB and other societies are urging the government to bring in policies to help phase out peat-based compost by 2015.
Are there Any Green Alternatives?
Though most gardeners seem in favour of making the environmentally-friendly switch, many are put off by the lack of widely available, green alternatives. However, there are plenty of viable, peat-free options on the market as well as home-produced alternatives.
Defra have announced that, though peat is best for some very specialist plants, for general garden use peat-free compost works as well, or better.
A recent Which? Survey found that peat-free composts actually performed better than peat-based rivals in the growing of potatoes and potted plants.
Emma Cooper, presenter of the Alternative Kitchen Garden podcast, has advocated the use of wood and food scraps as a viable alternative.
Many peat-free composts have a reputation for being unreliable. However, John Walker investigates this claim in his new book, ‘How To Create An Eco Garden’ and finds it to be false-at least in part. He recommends 6 peat-free composts as being the best in the market, which can be found on his website, www.earthfriendlygardener.net
He also says that your level of gardening experience should not prevent you from getting good results using peat-free composts.
A typical compost bin, used for home-produced compost. Image Credits: auburnwa.gov
Sources and Further Reading