In this exclusive extract from Compost, Charles Dowding shares a few simple tricks that will make a notable difference to the quality of your compost, making it easier to handle and quick to spread.
Chop up long stems and sticks
Too many woody stems more than 15cm (6in) long create a lattice effect in a heap, where large air spaces lead to very slow decomposition. The resulting compost is also filled with long sticks and strands, making it uneven and difficult to handle. Use a knife, secateurs, rotary lawnmower, or shredder to chop all woody material and tough, fibrous stems.
The best results are from pieces 5–10cm (2–4in) or less, which allow green and brown materials to bed down in contact with one another. These also increase the woody waste’s surface area for microbes to access and decompose. Use a knife to cleave tough brassica and sunflower stems down the middle lengthways twice, creating slimmer lengths that are easy to cut up.
The best results are from pieces 5–10cm (2–4in) or less, which allow green and brown materials to bed down in contact with one another. These also increase the woody waste’s surface area for microbes to access and decompose. Use a knife to cleave tough brassica and sunflower stems down the middle lengthways twice, creating slimmer lengths that are easy to cut up.
Working with woodchip
Woodchip from your own garden or local tree surgeons is a valuable source of brown material, but you should avoid using freshly chipped wood in a heap of mixed materials. This is simply because, even in small chips, the tough wood takes longer to break down than other waste in the heap and will still be there in your finished compost.
Instead, it’s much better to compost woodchip that is already partially decomposed, having spent at least six months in a separate, damp heap. To avoid large woody pieces remaining in your finished compost, remove them by running old woodchip down a 45° throw-through sieve before adding the resulting finer and partly decomposed material to the heap.
Instead, it’s much better to compost woodchip that is already partially decomposed, having spent at least six months in a separate, damp heap. To avoid large woody pieces remaining in your finished compost, remove them by running old woodchip down a 45° throw-through sieve before adding the resulting finer and partly decomposed material to the heap.
Managing moisture
In wetter climates like the UK we rarely need to add water to compost heaps, because most green materials already contain so much moisture that too many of them will result in a soggy, anaerobic heap. With sufficient layers of brown materials, moisture levels are naturally about right. Adding dry browns can even soak up excess moisture. Paper or cardboard are particularly useful for this, so don’t pre-wet them before adding.
By contrast, in dry climates, or during exceptionally hot and dry summer weather, garden waste contains less moisture and it’s often necessary to water your heap. Add water using a can or hose with a fine rose, with each addition of material that looks and feels dry. Stop adding water if weather conditions and materials become wetter.
By contrast, in dry climates, or during exceptionally hot and dry summer weather, garden waste contains less moisture and it’s often necessary to water your heap. Add water using a can or hose with a fine rose, with each addition of material that looks and feels dry. Stop adding water if weather conditions and materials become wetter.