The family Proteaceae, includes the macadamia, as flowering plants, with seven of the species native of Australia and one of the species native to Indonesia (Macadamia hildebrandii). The genus was named after John Macadam, whilst the Aboriginal people were aware of this natural nut and it’s many uses is was discovered by Allan Cunningham in 1828 and more people began to realise the potential of the macadamia as a commercial commodity.
A group of horticulturalists from America visited Australia in the early 1900s, and in tasting the macadamia nut, felt that the sensation of it’s taste would prove a winner, so the nuts/trees of the macadamia, were imported to Hawaii, and grown on the volcanic slopes. Hawaii has now become the world’s largest producer of the macadamia nut, often confused with the Hawaiian nut.
The common names of the macadamia include:- Macadamia nut, Maroochi nut, Bush nut and Queensland nut, however, wild nut trees were found originally at Mount Bauple which is near Maryborough in S E Australia and locals in the area refer to them as Bauple nuts.
Two of the genus appear to be most popular:- the smooth shelled (Macadamia interifolia) and the rough shelled ( Macadamia tetraphylla). The trees can grow to beyween 30 and 40ft in height, producing racemes (flowers) approximately 1/2 inches long but have no petals but 4 petaloid sepals in clusters of 6 to 12 inches long, creamy white with green leaves 8 to 11 inches long on Macadamia integrifolia, whilst the Macadamia tetraphylla flowers are cream or pink in colour that grow to 15 inches in length with leaves of green up to 20 inches long and part of the attraction of these trees is the flowers set against the green leaves coupled with the new growth, which is a bronzy pink.
Should you decide that walking to Hawaii is to far, just for a packet of nuts! you could contemplate growing a macadamia nut tree of your own. My suggestion would be to buy a mature macadamia nut tree as the nuts are not in great quantities on the younger plants, commercial quantities are produced when trees are 7-10years old, but once established macadamia trees can grow for over 100 years. In the early 1880s two seedlings of the macadamia trees were planted in the campus of Berkeley at California University and can still be seen standing.
Macadamia trees are best in a frost free- mild climate, (mature macadamia trees being fairly frost hardy) although tolerating temperatures as low as 24f. the clusters of flowers are usually killed off at 28f. and the young trees can be killed by light frost, whilst consistently high temperatures in summer will reduce macadamia nut yields, this is the information you should enquire about when visiting your grower/horticuluralist!
WARNING:- Macadamia nuts are toxic to dogs, and if eaten by your pet, macadamia nut toxicosis may result, signs are shown by weakness or the inability to stand within about twelve hours. Fortunately recovery from macadamia toxicosis is in approximately 48 hours.
I don’t want you to think of this as just another nut ( no! not me) but of the health benefits of the macadamia, the high fibre content of the nut (selenium and phytic acid) are associated with the reduction of cancer risk. Similarly, content in the nut of mono-unsaturated fats can help your cholesteral level, which helps in the reduction of heart disease.
Also think of the macadamia nut’s many uses :- in the use of cooking, muffins, bread, nut butter, savoury and sweet recipes, nut toffee, or just roasted or raw, coupled with the olive oil content, this is truly a health giving nut, worth growing.