Composting: a beginner's guide

Starting your own compost heap

Composting sounds complicated, but it really isn't. Basically, you pile up green and brown waste and let nature do the rest. Worms, fungi and bacteria break everything down into rich, dark earth. It doesn't smell bad when you get it right. It smells like a forest.

GardenWorld helps you visualise a garden design suited to your soil type. Know what you're planting and you'll know how much compost you need and whether your own heap is worth the effort.

Choosing the right bin

You don't need a fancy system. A simple wooden enclosure about a metre square works brilliantly. Garden centres stock ready-made compost bins in all sizes and prices. A closed bin with a lid keeps rats out. An open bin allows more airflow and is easier to turn.

Got a small garden? A worm bin fits on any balcony. It processes kitchen waste and after a few months delivers excellent worm castings.

The best spot

Place your heap in a sheltered spot with partial shade. Full sun dries it out too fast. Full shade slows decomposition too much. Directly on soil is better than on paving, so worms can move in easily.

The golden ratio

The secret to good compost is the balance between green and brown material. Aim for roughly two parts brown to one part green.

Green material (nitrogen-rich): grass clippings, kitchen waste, vegetable and fruit scraps, coffee grounds, fresh leaves.

Brown material (carbon-rich): dried leaves, cardboard, straw, wood chips, twigs, egg cartons.

Too much green creates a wet, smelly mess. Too much brown and nothing happens for months. The right balance smells earthy and feels about as moist as a wrung-out sponge.

What to keep out

Meat, fish, dairy and cooked food attract vermin. Diseased plants and seeding weeds can spread problems. Cat litter, dog waste and treated wood don't belong in there either.

Maintaining your heap

Turn the heap every three to four weeks with a fork. That introduces oxygen and speeds up the process enormously. Too dry? Pour some water over it. Too wet? Add brown material.

When is compost ready?

After six to twelve months, your compost is mature. It's dark brown, crumbly and you can't recognise any original material. It smells sweet and earthy. Can you still spot chunks? Sieve it and toss the coarse bits back on the heap.

Frequently asked questions

Can coffee grounds go in? Absolutely. Worms love them and they add nitrogen.

What about citrus peel? In small amounts, fine. Too much makes the heap too acidic.

Does compost accelerator help? It can shorten the process by a few weeks, but it's not strictly necessary if your ratio is right.

Tips for faster compost

• Chop large material small. Smaller pieces break down faster
• Mix briefly with each addition
• Keep the heap at least a cubic metre for optimal heat generation
• Start in spring when temperatures rise

Start today

Composting is free, sustainable and produces the best garden product there is. You reduce your waste and your garden benefits. Win-win. Plan your garden at GardenWorld and work out how much compost you need for a thriving result.