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Composting

 Composting

Composting



2005-02-28
Try not to use peat if you can help it. Britain's peat bogs are rapidly disappearing with the consequent destruction of wildlife. Two million tonnes of peat are sold to gardeners every year! Use home-made compost if you can or buy composted forest bark a renewable resource from managed plantations. A new product in garden centres is composted coconut fibre or coir. This consists of the outer husks of coconuts so it is an ecologically acceptable, renewable resource. Trials have shown it performs as well as peat-based compost.

Spent mushroom compost, spent hops (as a top dressing) and composted stable manure are alternative fertilisers.

Dried blood and fish meal are often used to add nitrogen to the soil, these are definitely not vegetarian products. You should also look out for various kinds of composted manures that are on sale these days, some even labelled organic as many of them contain manure from factory farmed animals or droppings from battery-kept chickens. Brands carrying the Soil Association's symbol come from free range houses.

Seaweed fertilisers are a good and acceptable substitute. Calcified seaweed however, is crushed coral, which is technically animal and besides, the way it is harvested is not good for the sea-bed environment! Bonemeal is a slaughterhouse byproduct. In addition to being non vegetarian, we hear that now organic growing is on the increase, bonemeal is being imported from South American countries where cattle ranching is helping to destroy the rainforest! There is no evidence yet that BSE might be transmitted through bonemeal, but in view of the uncertainties about the origin and transmission of this disease and the fact that the causative agent seems to survive heat treatment, this is something that should be taken into consideration. There is also the probability that bonemeal may actually contain the cremated remains of pet cats and dogs. Don't use a product called worm compost without investigating its source. Some methods of making it are acceptable, but others may cause injury to the worms, or even kill them.

If you make your own compost, you know what's gone into it so you can be sure that it is acceptable! Invest in a compost bin, or make your own, or if you are really short of space, use a heavy duty polythene sack. Put a shovelful of soil at the bottom to provide the organisms that start off the fermenting process, then add layers of kitchen waste, fallen leaves, grass cuttings and any other organic waste matter, even shredded paper will compost, used kitchen roll and paper hankies (if you must use them! There are more environmentally-friendly alternatives) will compost very easily. Tough things like cabbage stalks and banana skins should be cut into smaller pieces. Annual weeds can be put in whole but perennial weeds should have their roots cut off and discarded, never put any part of the plant bindweed into your compost, even small pieces will root and your garden will have a wonderful crop of bindweed when you spread the compost!

Make sure you don't add quantities of extra soil when you add weeds, it can slow down the fermentation process. If you are using the polythene sack method, tie the sack off when it is nearly full and pierce two or three air holes in the sides and leave to rot down until about a third of the original bulk is left, then turn out and spread on your soil. Most compost bins have provision for you to remove compost from the bottom without emptying the entire bin so the process can be continuous.

Some completely inorganic fertilisers are available, although frowned upon by the organic movement, they do have the advantage of being produced without any animal exploitation. Phosphate rock is mined from natural deposits and superphosphate is produced by treating it with sulphuric acid. Potash (potassium) is also mined from deposits of potassium chloride laid down when ancient seas dried up. Potash is suitable for immediate application and doesn't need further treatment.

Inorganic nitrogen fertilisers are based on ammonia, which in turn is made from nitrogen extracted from the air. The usual fertilisers are ammonium nitrate and ammonium sulphate, the latter is also a byproduct of the steel and manmade fibre industries. The Fertiliser Manufacturers' Association says that as far as it is aware, no animal testing of inorganic fertilisers is done in Britain as the fertilisers have stood the test of time and, if used properly, should do no harm. However, some foreign companies have carried out animal-based research.

If you have just treated your garden or lawn with an inorganic fertiliser, do keep any vegetarian pets like rabbits and tortoises from grazing on it until there has been a good fall of rain to wash the fertiliser in, concentrated fertiliser can poison if ingested. One of the objections to vegetarianism you sometimes hear is that without animal farming, there wouldn't be enough manure to make organic farming possible. People who think this forget about their own waste products. Human faeces can be safely composted without hazard to health if a simple process is followed. This provides a truly humane source of fertiliser, it saves the pollution of waterways and coasts caused by our present system of sewage disposal, it conserves plant nutrients one person's annual excrement is the equivalent of 25kg of commercially produced 20:10:10 NPK fertiliser. There is no real objection to using human excrement as fertiliser except in people's minds. For instructions on how to construct a simple, safe, odourless Eco-Loo contact the National Centre for Alternative Technology.

Plants of the pea family, including ornamentals like sweet peas and lupins, have the ability to fix nitrogen from the air. They do this by means of special bacteria which live in nodules in the roots, so after growing a crop of peas, beans, sweet peas etc don't pull the roots out when the plant is finished, dig them back into the soil to release the nitrogen.


Centre for Alternative Technology (CAT)
Information Department
tel: +44 (0) 1654 705989
fax: +44 (0) 1654 702782

Machynlleth, Powys, SY20 9AZ, Wales, UK
Website: http://www.cat.org.uk


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