The Garden produces a vast amount of green and wood waste every year. Until recently we recycled and reused this waste on site, creating a sustainable closed loop.
Green waste, which includes everything from twigs, branches, and leaves to grass cuttings, is recycled through composting. This raw material is stockpiled. When there is sufficient, we hire a large shredding machine which cuts and smashes the waste into small particles ready for composting. Through the action of bacteria, the shredded waste starts to breakdown heating up in the process. The compost heap starts to steam, and can reach 70—80°C, enough to kill weed seeds and pests. Turning the heap helps create even heat and effective breakdown of the material. Some 4-6 months later the compost has cooled and matured ready for use. It is spread onto beds and around plants as a mulch. This improves soil structure and helps retain moisture, encouraging healthy plant growth.
Most wood is processed into wooden chips which can be used to mulch beds and top-dress informal paths. Some pieces of wood may be used for sculpture, timber or processed as firewood, ensuring nothing is removed from the site.