What is Composting?
Composting is the conversion of biodegradable, organic matter into compost. The “raw material” could be kitchen, home or garden waste and the result is a nutrient-rich fertiliser. Composting is an entirely natural process, but you can speed it up by providing an environment where decomposers can flourish.
What is a wormery?
A wormery is a system of converting organic matter into compost with the help of earthworms.
Why should I compost?
Composting is environmentally friendly – about 60% of all household waste is organic, so recycling this waste will help reduce the volume of waste in British landfills and waste-disposal lorries on the roads. In 2004, WRAP (Waste and Resources Action Programme) launched a Home Composting Campaign. The aim was to get a million Britons composting at home, thus diverting 400,000 tonnes of waste from landfill – an amount not to be sniffed at!
Compost, the by-product of composting, is an excellent fertiliser, which improves soil structure, water retention and drainage in the garden. Some composting systems allow you to collect liquid fertiliser, an excellent plant feed when diluted with water. Best of all, composting is free.
What should I compost?
All biodegradable material eventually decomposes, and it's surprising what can be added to your compost heap:
- Kitchen waste - vegetable peelings; food scraps; egg shells; teabags and coffee grounds.
- Home waste - dust from the vacuum cleaner; hair; eggboxes; newspaper; toilet/kitchen rolls.
- Garden waste – prunings; grass clippings; leaves.
- Animal waste - manure; bedding like sawdust, shavings or hay.
A small-scale composter does not produce sufficient heat to kill all bacteria. So avoid the following compost “ingredients”:
- Manure from non-vegetarian animals (e.g. cats or dogs)
- Meat/fish scraps; dairy products
Also avoid pernicious weeds (e.g. bindweed, couch grass) as these are very difficult to eradicate once established in your garden.
For efficient composting, you need sources of cellulose (carbon) and protein (nitrogen):
- Sawdust / wood shavings
- Dry leaves
- Cardboard and newspaper
- Grass cuttings
- Leafy weeds
- Animal dung (chicken manure is especially good)
- Fruit / vegetable peelings
and if you live on the coast, seaweed is an excellent compost ingredient!
Why should I compost with Worms?
When initial bacterial action has slowed, your compost heap will cool down. There's still a lot of decomposition to be done, though, and this is where worms come in. Able to eat their own bodyweight of organic matter in one day, they help finish the job of composting.
Worms are beneficial because they:
- work quickly – nature's fastest composters.
- can reduce the compost's volume by 85%.
- produce vermicompost - a quality fertiliser.
- operate effectively on small volumes of waste.
- help prevent odours.
Can I collect worms from my garden?
Well, you could, but you'll have a happier, healthier compost heap if you use specialist worms. The worms in your garden are most likely to be Lumbricus terrestris, lob worms, which are deep-burrowing and unsuited to compost heaps. For an effective wormery you need lots of worms – about 1 kg per cubic metre – but you only need to buy worms once. Your colony will breed prolifically and will then regulate itself to suit the amount of waste provided.
The best and most commonly available species for composting are litter dwelling worms:
Dendrobaena veneta - a striped worm and a voracious eater. The natural habitat for these worms is a woodland floor, so they will thrive on leafy waste.
Eisenia andreii / fetida – also known as the Red Tiger worm, this species is perfect for composters due to rapid breeding and waste consumption rates. Smaller and less hardy than the Dendrobaena, Eisenia worms are also more sensitive to changes in the environment.
Lumbricus rubellus – a redworm like Eisenia, Lumbricus can survive at lower temperatures than other worms, though the amount of food eaten will decrease significantly below 10 degrees Celsius. Though a surface dweller like Eisenia, Lumbricus can tunnel into the soil more deeply, making it a good choice for outdoor compost heaps and cold winters.
Will it be labour intensive?
An established compost heap or wormery will take care of itself. Gathering garden leaves and clippings, and carrying household waste to the heap will require a little effort, but by and large composting is not hard work. You do need some patience at first as heaps take 6 – 9 months to get established. But it's worth the wait - the average kitchen annually produces 200 kg of organic waste, a lot of potential compost for your garden!
Ready-made systems like Can-O-Worms from Wiggly Wigglers make life even easier – simply remove the bottom tray when it's full of wormcasts, harvest the vermicompost and return the empty tray to the top of the stack.
Will it smell?
A healthy compost heap won't smell, especially if you include worms in your composting system. Stopping your compost from getting too wet will help minimise smells, and mineral powders can be added if the problem persists.
Where can I buy composting equipment and worms?
All you really need for a compost heap is a bin and plenty of organic waste. Bins are available at garden centres and hardware shops. When choosing a bin, look out for:
- Size – composting is more efficient if your bin is full so don't buy an oversized bin.
- Colour – the darker the better, to absorb heat.
- Shape – a cone shape is best for drainage and air-flow.
- Ventilation – it's a myth that air holes are necessary for composting. With the right mix of waste, your heap will be sufficiently aerated. Holes in the bin slow down the process by releasing thermal energy.
Log on to www.recyclenow.com to see whether a low cost compost bin offer is operating in your area.
To build a wormery, you will need:
- 1-2 kg of worms
- coir bedding
- moisture matting
- lime mix
Where can I get advice?
WRAP has a team of Home Composting Advisors, each dedicated to a specific UK region. You can contact them on 0845 600 0323.
More helpful information is available from: