Macadamia nut, Smooth-shelled Macadamia
Macadamia integrifolia

Family: Proteaceae

What it is like

A medium size evergreen tree. It grows 18 m tall and spreads 15 m wide. It has a bushy habit. Young growth is pale green. Young leaves are long and toothed at the edge. Leaves are 10-20 cm long by 3-5 cm wide. They occur in whorls or rings of 3 or 4 leaves. They are stiff and dark green. The leaves are entire with a wavy or slightly prickly edge. Flowers occur in clustered stalks 10-30 cm long. They occur in the axils of leaves and hang downwards. The flowers are about 1.2 cm long. They are slender and white. The fruit are 3-4 cm across and green and leathery. The nuts are produced in a hanging cluster. They are 2-3 cm across and round. They are smooth and shiny.

There are about 14 Macadamia species. They are mainly in Australia.

Where it is found

It is a subtropical plant. It grows in the highlands in the tropics. It is native to Australia. In Australia trees grow naturally in rain forests in the subtropics. It suits humid locations. Soils need to be well-drained. They need a sheltered site as they suffer from wind damage. They do best in humus rich soils. They can tolerate light frosts. It has been introduced to other countries from Australia. It does well at 1000 to 1200 m altitude in Papua New Guinea and will grow up to 1700 m. In XTBG Yunnan. It suits hardiness zones 9-11.

Countries/locations it is found in

Africa, Asia, Australia (country/location of origin), Brazil, Central America, China, Colombia, Cook Islands, Costa Rica, East Africa, Ethiopia, Fiji, Guam, Guatemala, Hawaii, Indochina, Indonesia, Kenya, Malawi, Marquesas, Mexico, North America, Pacific, Peru, Philippines, Samoa, SE Asia, Singapore, Solomon Islands, South Africa, Southern Africa, South America, Tanzania, Thailand, USA, Venezuela, Zimbabwe

How it is used for food

The nuts are eaten raw although some kinds are roasted. They can be coated with chocolate or carob and used in pastries, candies, ice cream, cakes and pies. The oil can be used with salads and stir-fried dishes.

Introduced into Papua New Guinea. Although not yet common in Papua New Guinea it is probably one of the nuts worth promoting. This is the commercial species. It is a cultivated food plant.

Edible parts

Seeds kernel, nuts

How it is grown

Trees are mostly grown from seed. Seed should be sown fresh. Seeds germinate quickly and easily. They can be grown from cuttings. Plants can be grown by budding or grafting. Pruning increases branching. A spacing of 5 to 10 m is suitable. Many varieties need pollinator trees and bees to assist pollination.

Nuts are ripe from January to March in Australia. Nuts are harvested after they fall. The outside husk needs to be rubbed off then the nuts dried in the sun.

Its other names

Local names

Bauplenut, Bopplenut, Bushnut, Castanha-macadamia, Mutebvu, Poppel Nut

Synonyms

Macadamia ternifolia var. integrifolia (Maiden & Betche) Maiden & Betche;