Macadamia integrifolia
Maiden.&Betche.
Macadamia, Macadamia nut
(c) Stephen Thorpe, some rights reserved (CC BY-NC), uploaded by Stephen Thorpe
(c) Emma, some rights reserved (CC BY-NC), uploaded by Emma
(c) Rob Palmer, some rights reserved (CC BY-NC-SA), uploaded by Rob Palmer
What to Eat
Edible parts: Oil, Seed
Milk Oil. Seed - raw or cooked. The fine, crunchy texture, rich cream colour and delicate flavour make the macadamia nut one of the finest dessert nuts. The eating quality of the nut is enhanced by lightly roasting it in coconut oil and salting .Sweet and delicious, the seeds can also be added to cakes, biscuits, ice cream etc. They can be ground into a flour and then added to cereals to enrich their protein value. The shell is very hard, making it difficult to extract the seed. The seed is up to 3cm long and wide. An edible oil can be obtained from the seed, though it is seldom extracted due to the high value of the seed The seed contains the highest level of oil yet found in a nut - up to 75%. The oil contains 80% monounsaturated fats and 8% omega-6 fatty acids. It has a subtle, nutty flavour and is added to salads, used in cooking etc.
Where to Find It
Australia - New South Wales, Queensland.
AUSTRALASIA: Australia, New South Wales (northeast), Queensland (southeast),
How to Identify
Macadamia integrifolia is an evergreen Tree growing to 10 m (32ft) by 10 m (32ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 9 and is frost tender. It is in leaf all year. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.
How to Grow
It grows best in areas where annual daytime temperatures are within the range 10 - 26°c, but can tolerate 8 - 35°c. Mature plants are capable of withstanding mild frosts, but only for short periods. It prefers a mean annual rainfall in the range 1,000 - 3,000mm, but tolerates 700 - 3,500mm. Requires a sunny position. Plants grow best in rich, moist but well-drained soils and require copious summer watering in their early stages. Prefers a pH in the range 5 - 6, tolerating 4.5 - 7. Established plants are very drought resistant. Trees require a sheltered position and are easily damaged by strong winds. Floral initiation takes place when temperatures drop and trees become quiescent in autumn, the optimum temperature being 18°c. The initials remain dormant for 50 - 96 days; the racemes extend after a rise in temperature and some rain. Seedling growth is initially slow, but gathers momentum as saplings produce a series of extension growth flushes in a year. The juvenile phase lasts for 7 years or more, but grafted trees come into bearing after 3 years. Plants are slow growing in cultivation, especially when young, seedlings take 6 - 7 years to produce their first fruit. The trees then produce commercial crops for about 40 - 50 years and can fruit for up to 100 years. The trees can flower and produce fruit all year round. Yields of 45 kg nuts-in-shell from better trees or an average of 3.2 - 3.5 t/ha per year are obtained in Hawaii. Pruning is not normally necessary, but is tolerated if carried out in the autumn. There are some named varieties.
Propagation: Seed - best sown as soon as it is ripe in a warm greenhouse. The dehusked seed germinates quickly at 25°c. The seed can also be sown in the spring in a warm greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. If trying them outdoors, give the plants some protection from the cold for their first few winters. Cultivars may be grafted.
Other Uses
Cosmetic Fuel Oil Plant breeding Tannin. Agroforestry Uses: The decomposed husk is commonly used in potting soil. Macadamia will retard the growth of papaya trees planted near to it. Other Uses: Macadamia shells may be used as fuel, generating sufficient energy to dry wet, in-shell nuts. The oil from the seed is used in cosmetics. The green seed hulls contain approximately 14% of tannins.
Names & Synonyms
Macadamia, Smoothshell, Queensland Nut
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