Making compost Composting tips

How to make great compost

A tester filling up a compost bin

You can start composting at any time of year

Start immediately 

You can start composting at any time of year, but spring to autumn is when you’ll have the most waste to add to your heap.

Get a cheap compost bin 

Some councils sell compost bins more cheaply than garden centres, and deliver to your door. Call your council to find out what’s on offer. 

Site your bin on bare soil 

This gives all the helpful soil organisms access to the heap to start the decomposition process.

Fill your bin 

Fill your compost bin with an equal volume of nitrogen-rich and carbon-rich material.

Nitrogen-rich (green) material includes:

  • Grass clippings – mix them in well with dry brown materials
  • Shrub prunings, shredded or finely chopped
  • Bedding and container plants after they’ve died off
  • Fresh farmyard manure
  • Raw vegetable remains
A tester adding grass to a pile to make compost

Adding similar amounts of green and brown waste is the key to making good compost

Carbon-rich (brown) material includes

  • Autumn leaves
  • Shredded paper
  • Straw and hay
  • Cardboard torn into small pieces
  • Flower stalks
  • Woody clippings

Do NOT add

  • Cooked food
  • Perennial weeds and weeds in seed
  • Diseased plants
  • Glossy paper
  • Soot
Phase 2 of making compost

Shred large, tough material before adding it to your bin

Shred large materials

Shred or chop any large, tough material before adding it to your bin so composting organisms can get to work on it quicker. If you don’t have a shredder, chop using a sharpened spade on a soft surface or simply use a pair of secateurs.

Keep your compost heap moist

Squeeze a small amount of compost in your hand; if it holds together and doesn’t drip it’s just right. Add a little water every time you add new material to your bin and check it’s moist when you turn it.

Turn your compost heap 

You should do this at least once every couple of months. Make sure you mix the edges into the middle when you turn the heap and add water if it’s dry. Turning is not so important in winter.

Compost problems solved

Wet heap

Phase 3 of making compost

Add bulky, dry materials to banish bad smells

The main cause of a soggy heap is too many grass clippings. Before adding grass, mix it with dry brown materials – save autumn leaves for this purpose. 

Smelly heap

An ammonia aroma is caused by too much green waste and a rotten smell is probably because the heap is too wet. Both are solved by adding bulky, dry materials such as leaves or straw and mixing well. Keeping a balance of green and brown materials and turning your heap regularly will minimise nasty odours.

Pests

Uncooked food is a good source of nutrients, but it’s also a delicacy for rats. If you add food to your heap, bury it deeply and keep your heap covered. If pests are a real problem, don’t add any food wastes at all.

Incomplete decomposition/dry edges

The usual cause of incomplete decomposition is a dry heap. Empty your bin and refill it making sure the edges are turned into the middle. Water if it feels dry. Your heap should be damp to the touch.

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