Vermicomposting organic waste is an environmentally friendly and sustainable method of dealing with an organic waste problem, it is equally effective in small or large domestic, agricultural or industrial situations with the benefits of comparatively little capital outlay and low management and maintenance costs.
The basic principles are the same in all situations and that is the waste is added to a bed of material that contain sufficient worms to digest the organic matter.
First a few facts that are worth noting:
– Worms will consume between 50% and 100% of their own weight in food per day.
– They will digest anything that has ever lived.
– They multiply rapidly.
– Worms do not get diseases.
The worms
There are many different species of worm but the worms used in waste recycling are all compost or litter worms, these are worms that live on or just below the soil level, feeding off the decaying organic materials on the soils surface, they do not burrow to any great extent. The ones that are found in most domestic compost heaps are Eisenia foetida also known as Brandlings or Tiger worms, Eisenia andrei and Dendrodrilus rubidus these, combined with the much larger Eisenia hortensis, a native to Europe and Asia, also known Dendrobaena, are an ideal combination, Eisenia hortensis is larger than Eisenia foetida and Eisenia andrei and thrives in a wide range of conditions.
Composting
Has been practised since man needed to return goodness to the soil. Traditionally the tried and tested method of inducing aerobic decomposition of piled organic material has been the widest employed method be it in a heap or in a composting bin. This method has certain drawbacks, rarely does the material compost equally throughout the pile even when turned, it may take a long time due to adverse weather conditions or lack of balanced ingredients, it can attract vermin and flies, it can have an offensive smell and the end result can be difficult and unpleasant to handle with little or no nutrient content.
Anybody who has had a compost heap that has been invaded by worms will recognise the immediate benefits. History shows that our predecessors have used worms to assist in the composting of organic matter but had little understanding of why they were so effective. More recently, studies into this fact have been carried out in many countries across the globe, the results of these studies show that there are far more benefits to using worms in the process of recycling organic matter, not only at the domestic level but also in large scale agricultural and industrial situations, than at first appreciated.
The benefits
First and foremost worms are an environmentally friendly and sustainable method of dealing with organic material. In working they do not use or need additional fuels whether man made or fossil, if properly managed they do not wear out and need replacing, they work 24 hours a day with very little input by man, they work in a wide range of conditions and automatically adjust themselves to these conditions.
When organic material is placed on the surface of a bed of worms it is already beginning to decay, it is being invaded by myriad bacteria, fungi, micro life and larger creatures, some of which along with the decaying matter are food to the worms, after digesting, it is excreted as “casts” earthworms often leave these as little curly mounds of soil on the surface, particularly in grassy areas. These casts are rich in nutrients and microbial life, when produced in a worm composting system they are harvested along with any compost left and the whole lot is a living world of goodness to any plants that receive it either as compost dug in or as a mulch on the surface, naturally growing plants and trees benefit from this all the time, unless man has interfered, rarely do you see naturalised plants suffering from nutrient deficiency.
As long as there is damp organic matter present, worms will continue to feed, breed and grow, they will multiply to the amount of food available and the original volume of organic material added to the bed can be reduced by as much as 90%.
What can be composted?
Worms feed on the micro organisms that are responsible for the decay in organic matter, any organic matter will grow these organisms, some materials are better than others, some are so slow they are best avoided all together, as the saying goes “if it has ever lived, worms will compost it” to be more accurate it should be “if it has ever lived, it will rot and worms will find a meal!” In the domestic situation we are looking at kitchen waste, garden waste and often overlooked, paper and cardboard. Kitchen waste should really be limited to vegetables, raw or cooked the exception being any vegetable that is a member of the onion family, including leeks, these must be thoroughly cooked first and mixed with other materials. All fruit can be fed to worms but again all citrus fruit will need thoroughly cooking, particularly the peel, when citrus fruit is fed raw it is often assumed that it is the acidity of the fruit that causes the problem to the worms, this is not necessarily the case, all peel has a substance called “d-limonene” (the vapour that sprays out when you are peeling it) it is harmful to worms but is driven off when thoroughly cooked. Cooking and “mashing” all fruit and vegetables is to be recommended, it will decompose faster, provide a bigger surface area on which the micro organisms can grow and is therefore processed quicker by the worms.
Used tea bags, coffee grounds, small quantities of bread can all be fed. Avoid dairy products, fat, grease and oil, meat and fish and bones, not because the worms will not compost these items, they will, but they will attract unwanted pests, flies etc.
Any decaying organic matter that is really smelly (not a problem to the worms!) once the worms start to process it, the smell quickly disappears, if a worm system is working effectively there is no smell.
Garden waste such as leaves, dead plants, grass clippings etc can be put into a worm bin but this usually slows the whole system down, particularly when woody material is involved, large quantities, certainly with grass clippings can cause real problems, even with small gardens the amount of waste after an afternoons gardening will overload the average domestic worm composting system, by far the best method is to pre-compost these materials in a traditional compost heap or bin and then feed the partially composted material to the worms, this way the micro life is already well established and the worms can deal with it much quicker, the same applies to the rabbit or guinea pig hutch cleanings.
Newspaper, office paper, paper bags etc (avoid glossy magazines) cardboard can all be shredded and added to the system, in fact this material plays an important part in providing the worms with a balanced micro life diet! Paper and cardboard are also helpful when the bin has become too wet by mixing in shredded paper or cardboard it will absorb some of the moisture and aerate the bin.