Mini Beasts

Fruit flies
These are tiny white or brown flies no more than 2 mm in length. They can appear as a cloud when the compost bin lid is removed. Anyone who puts fruit and vegetable wastes into their bin may encounter these at some point during the summer. They are totally harmless and are part of the composting process, feeding on the fruit acids contained in the material. To discourage them bury your fruit waste underneath the garden material or wrap it in newspaper. A thin layer of soil will temporarily suppress their population.

Woodlice
Another decomposer organism, in this case specialising in breaking down the cellulose fibres contained in woody material such as hedge clippings. Again, perfectly harmless and should be no cause for concern.

Worms
Categorised as secondary decomposers, these organisms move in when the fungi have completed their work. There are two main types of worm, Earthworms and Tiger worms. The main difference between them is that Earthworms are burrowers and live in the soil, whereas tiger worms live within the nutrient rich decomposing material.

Fungi
Many types of fungi live in the compost bin. These are primary decomposers and get to work on the material immediately. Their presence is sometimes mistaken as a sign that all is not well. However if fungi forms mushrooms on the surface of the composting material, this denotes a healthy compost bin.

Slugs and snails
Two examples of decomposer organisms that are seen as pests in other parts of the garden, but are helpful in the compost bin. Compost bins can be seen as breeding grounds for slugs and snails and as a result people can be discouraged from composting. Whilst there are no guarantees that they will not be tempted to move to other areas, the compost bin offers a number of advantages. In particular a plentiful food supply in a secure environment. On no account should slug powder or pellets be used in the bin as this would kill other beneficial organisms.

Ants
Occasionally ants can set up a colony in a compost bin. They do not harm the composting process, in fact by making burrows in the material they provide air passages as well as breaking down some of the material itself. Generally, their presence will indicate that the mix is too dry. As with slugs, no poison should be used to remove them. Spraying the ants with cold water will encourage them to leave, do not use boiling water as this would kill many other beneficial organisms.

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