Most gardens produce waste such as twigs and branches from pruning woody plants. This can be troublesome to dispose of in a way that is kind to the environment and to neighbours. Unlike burning, composting is the ideal solution and results in a usable organic material for the garden.
Suitable for...
Any woody clippings, stems, twigs, and smaller branches can be composted in the garden without resorting to burning.
Larger branches, tree trunks and stumps are less suited to composting but can be turned into wildlife-friendly log piles which ultimately rot down in the garden.
When to compost woody waste
In small gardens woody wastes cannot be stockpiled and has to be dealt with promptly. In larger gardens prunings can be left for disposal at a convenient time, typically in winter when there are fewer jobs to do.
How to deal with woody waste
Woody waste can be dealt with in a number of ways, depending on its size.
Hedge trimmings and other slender growth:
- Where small quantities are involved, woody materials can be snipped up and deposited back on borders and beneath hedges, or indeed consigned to the home compost bin. They will disappear surprisingly quickly
- For greater quantities, passing them through a shredder is best. Most domestic shredders will cope with woody stems less than 3-4cm (1¼-1½in) in diameter. The resulting fragments can be used to mulch around established beds or heaped up to compost for later use
- Many shredders only mill timbers and it may not produce fragments. However, milling will speed up decompositiong very effectively even though timber remains rather stringy
- Being rich in carbon but low in nitrogen, shredded material will require mixing with nitrogen-rich materials such as lawn mowings to increase the rate of rotting
Thicker branches:
- Heavy duty shredders can be hired or contractors with access to such machines can be engaged. These will quickly reduce any timbers to fragments for disposal off site or, better still, used as mulch or composted within the garden. This is an option for big gardens or major tasks
- Adding nitrogen-rich materials such as grass clippings is even more important to speed rotting of thicker branches as these are proportionally even richer in carbon than thin woody stems
- Unprocessed heavier timbers can be cut into lengths and stacked. When left to rot in their own, rather prolonged time, these log piles make excellent refuges for wildlife. This requires some space but is very beneficial for biodiversity within a garden
Alternative methods:
- Some timbers have potential, when sawn into logs or cut up as kindling, as fuel in open fires and log-burning stoves
- When dry, slender woody stems burn well in bonfires. However, bonfires are a less productive way of using this resource and also have the potential to annoy neighbours unless conducted when wind and weather mean that smoke will not enter houses or inhibit others enjoying their garden
- Garden contractors will remove and dispose of woody wastes
- As a last resort light timbers can be bagged or bundled and taken to a green waste disposal site (seek guidance from your local authority)
Hiring or buying shredders:
Whether to hire or buy a shredder really depends on how much use you anticipate making of it. For gardens with a lot of twiggy material from hedges, spent fruit canes and shrubs, it is probably worth buying an electric-powered shredder. These are relatively quiet to use and effective on smaller stems. It is more economical, however, for gardens with thicker or occasional prunings such as from fruit trees to hire a petrol-powered shredder once or twice a year.
Safety first:
Always ask the hire company for a demo or use the manufacturer’s instructions before operating garden shredders. Wear gloves and goggles to protect eyes from flying debris. Never try to force material through the shredder or unblock jams by putting your hand into where there are moving parts. Many shredders can be unblocked by putting them into reverse.
Where to use composted woody waste
Woody waste has a number of uses;
Freshly shredded material: is suitable for spreading on unplanted areas such as paths or to suppress weeds around shrubs and plants. Conifer prunings, however, release tannins which can be harmful to plants so compost these first for three months by stacking in a big pile. Take care not to bury herbaceous perennials or small bulbs with woody mulch.
Woody material that has been composted for a minimum of 12 months and is brittle and rotted: can be dug into the soil to improve structure.
Problems
As bark mulches rot down, it is not uncommon to find them colonised by white fungal growth or covered in a crop of toadstools. Thankfully these belong to saprohpytic fungi that are harmless to plants; they are simply breaking down the organic material. No action is required.