Growers ensure every part of the macadamia tree and nut is either reused or recycled, with nothing going to landfill.
Organic matter such as branches or foliage is returned to the earth beneath the trees to be reabsorbed by the soil from which they originally grew, while the soft outer husks of the macadamia nuts are used as compost. This on-farm recycling enriches the soil with nutrients and helps to naturally sequester carbon in the ground.
Macadamia shells are a valuable resource and can be re-used in many ways after the macadamias have been cracked, including for electricity generation. One of Australia’s largest macadamia suppliers burns its macadamia shells in a specially controlled environment which not only creates heat to dry the kernel, but also powers its cracking plant.
Macadamia shells can be used to create biochar, a natural high-carbon fertilizer, by burning them at a high temperature in a low oxygen environment. They can also be used to make building products, carbon filters and industrial nano-powders, while medical charcoal derived from macadamia shells has been used as an effective hospital treatment for poisoning.
Watch below to see how artist and craftsman Marc Harrison features both macadamia shells and wood in his unique homewares and furnishings.