Home composting guide

Tips to make great compost

Where to place your compost bin

If it’s a plastic bin with a lid, it will be less prone to drying out and the heat of the sun can be helpful in speeding up the breakdown process. If you have an open bin or box, it's better to keep it in at least partial shade. Try and keep your bin out of the wind, so it's easier to turn it without material flying away on a windy day. Don’t place it on hard standing as it works best on soil.

If your compost smells bad

Don’t put cooked food scraps, meat or dairy waste in your compost. If it still smells, that’s probably due to excessive moisture. If conditions are too damp, this encourages the activity of anaerobic microorganisms, which do not need air and tend to create smelly substances as a by-product of their activity.

Turn the heap and add more dry or woody materials, such as fallen leaves or small pieces of cardboard.

If your heap isn’t getting warm

It might be too dry, so add more wet materials like soft garden waste, vegetable or fruit peelings or you could pour on a few pints of water. You can also try shredding materials more finely, which increases the surface area of the particles and speeds up their decomposition. Don't worry too much about the temperature - even if the heap isn't steaming hot, the compost process will still take place: it will just take a little longer.

Avoid attracting vermin

If you don't put cooked foods, starchy foods, meat or dairy scraps on the heap, there shouldn't be anything there to attract either pets or vermin. Put a rock on the lid or cover the top of the heap with a piece of old carpet to make it less accessible. The base of the compost bin can be covered with fine mesh chicken wire to prevent vermin from entering the bin from underneath while still allowing beneficial creatures such as worms to get in.

If you put on lots of fallen fruit or fruit peelings in the summer, wasps and bees may start hovering around. Try burying fruit scraps in the middle of the heap. Turn it regularly to speed up decomposition.

Too many grass clippings

Whether your compost heap can handle large amounts of grass clippings depends on how big it is and on what else is in it. Large amounts of clippings dumped on a small heap tend to turn into green slime rather than crumbly compost. Stirring and turning the heap to incorporate the clippings makes better compost, as does mixing in dry materials such as leaves or cardboard. The best way to deal with grass clippings is to cut the grass frequently and simply leave the clippings on the lawn to nourish and protect the roots. You can also join the garden waste collection service or take excess clippings to the household waste recycling centre.

Using activators, accelerators or lime

Activators, or inoculants, which provide short-term infusions of nitrogen, are not necessary. It’s better to mix in manure, leaves, grass clippings or even bone meal, which deliver a slow release of nitrogen over time and are less likely to wash out and contaminate the ground water.

Adding lime is not recommended, because it can cause nitrogen to be released in the form of ammonia gas. You don’t have to worry about the pH of your compost heap –it generally adjusts itself and stays around neutral (pH7). If necessary, the pH can be adjusted when the compost is finished, after a pH test.