Composting

It's a waste to waste waste

Every year in the UK households send nearly 30 million tonnes of rubbish to be buried in landfill sites. Landfilling our waste is expensive and uses up precious land and other resources. Up to 40% ofthe waste going to landfill is green waste, stuff that could be could be diverted for garden composting or special green waste processing centres.

Dying to be recycled

When plants or animals die, they rot away, or decompose, helped by bacteria, fungi, plants, animals and the weather. Dead remains, or detritus, which include things like droppings, shedded hair or leaves, are turned into humus (the organic part of the soil) and into the bodies of the organisms feeding and living on them. The same process works for other things made originally from plant or animal materials, like woollen clothing or paper. These materials are called organic because of their chemical ingredients and origin. (Confusingly, this is not the same word organic that you see in the shops used to descibe food or crops grown in a particular way!)

So if we mix suitable ingredients, layered in the right way, we can speed up this process of natural recycling to produce lots of lovely, useful compost. You can make compost by building a heap or using compost bins like these shown here. The instructions on how to make them are below.

Dustbin
Cut the base off a plastic dustbin, turn the dustbin upside down and replace the lid.

Wooden and wire bins
Drive four wooden posts into the ground to make a square 90cm x 90cm. For a wire bin staple chicken wire to the posts and line sides with cardboard. To make a wooden bin nail wooden slats along three sides. Keep the fourth loose for access. With either bin you can use a peice of old carpet as a lid.

Cool compost at home
Most people add a bit of material at a time to their compost bin or heap, gradually building up layers. The ingredients list can help you decide what kind of things to layer together.

The important things are to include both soft and tough material, to keep heat in and not to let the heap dry out.

The right mix will leave plenty of air spaces. Too much soft stuff makes things go slimy, too much tough stuff takes ages to compost! Your compost is ready when it has turned dark brown and crumbly and it smells earthy.

School schemes

If your school has a garden, why not start composting there?  Garden waste could be used along with tea bags from the staff room, apple cores from lunch boxes and some waste paper.  If you have school kitchens, they could help too with potato peelings and other raw vegetable waste!

Once you have made your compost heap, inspect it every couple of weeks to see if it’s too dry (add water or more soft stuff) or too wet (mix in shredded paper, cardboard and air).

Compost community - Who eats what at the Compost Café?

Compost heaps should be teeming with life - especially the minibeasts that munch their ways through all the ingredients, turning them into smaller and smaller pieces. The bacteria and fungi that are even more important in the composting process are microcopic.

Dish of the day

Everything living in the heap will be on the menu for something else sooner or later! Even the recyclers are recycled.

Some of the most familiar residents of your compost heap will be woodlice. These detritus eaters have to keep a film of water over their gill-like breathing organs. Brown, yellow and/or orange Brandling worms (Eisena foetida) feast on the composting material and produce a foul smelling fluid when you disturb them.

Feast and sleep

Hedgehogs and toads visiting the heaps will eat the worms as well as other invertebrates. Either of these species may also choose to hibernate in the dryer parts of your heap - very cosy with endless snacks if they wake up! (If you are emptying a compost heap between November and March keep a sharp eye out so that you can avoid harming snoozing animals).

Snacks and snails

For vegetarian slugs and snails which glide about on their own mucus trails, a damp compost heap is an ideal home. When the weather is too hot, too cold or too dry they wait in the heap until things improve. Where conditions are right, many of them gather together for a spot of lively nightlife!

Snakes alive

In England or Wales, if you are lucky, an adult female grass snake may lay her 30-40 eggs in your compost heap during June or July. The warmth created by the decomposition going on of the heap helps the eggs develop, and young snakes find food on their doorstep when they hatch. Several snakes may lay in the same suitable spot - the record is 1,200 eggs in one heap. Grass snakes are harmless to people.

Beetle mania

By midsummer, compost heaps are alive with insects and their larvae. There is plenty to eat for the hunting ground beetles (such as Pterostichus madidas and Trechus quadristriatus) and rove beetles (including the devil’s coachhorse and Hister quadrimaculatus which “plays dead” if you disturb it).  Stag beetles are usually only found in the south and east of the UK and traditionally their larvae develop in tree stumps. The importance of compost heaps to them may lie in the fungi which grow there. The earwigs Labia minor and Forficula auricularia eat almost anything, plant or animal, alive or dead! Brightly coloured soldier flies, such as Microchrysa polita, breed in compost heaps.

Caught in a web

The webs of garden spiders, may be built anywhere including close to the compost heaps to catch flying insects. These are most numerous and easily spied in the late summer when they can be seen laden with dew in early mornings.  Like the spiders, centipedes, equipped with poison claws, dine only on the other diners whilst their relatives, the millipedes eat mostly plant materials. The cyanide or chlorine they emit puts off predators like centipedes, but is no good against hungry birds.

Bird biodiversity

Blackbirds and robins will often watch when you are turning your heap, or spreading compost on the garden, waiting for wriggly snacks as soon as you move away. Making compost helps the environment by reducing waste, enriching the soil for plants, and helping wildlife by providing food and shelter.