Macadamia ternifolia aka Australian Nut

Macadamia ternifolia is an evergreen tree in the Proteaceae family. It comes from southeast Queensland, Australia, where it is native. Common names include Gympie nut and small-fruited Queensland nut. The RHS also lists the name maroochie nut for this species. Kew places it in the wet tropical biome. Its natural range does not include Britain or Ireland.

Plants For A Future describes a tree with a moderate growth rate. It reaches about 26 feet (8 metres) in height. Its spread reaches about 20 feet (6 metres). The tree keeps its leaves throughout the year. The supplied sources give no details of leaf shape or bark. They also give no flower colour or flowering season. The account notes that trees can live for over a century.

In the wild, it grows in gullies on south-facing slopes. These sites have fertile soils formed from basalt. It also grows where sandstone meets basalt-derived soil. Recorded sites range from about 328–1,050 feet (100–320 metres) above sea level. Most lie below about 656 feet (200 metres). Slopes at these sites range from moderate to steep. This habitat account gives useful context for its need for drainage.

In cultivation, it needs an open site rather than shade. Plants For A Future recommends fertile soil that drains well. Sandy loam through light clay suits the tree. The same source lists tolerance of sandy, loamy and clay soils. It prefers moist ground, with a pH of 5.5–7.0. This spans mildly acid to neutral conditions. The listed USDA hardiness range is zones 10–12. These warm-zone ratings limit its use in colder outdoor gardens.

Plants For A Future lists the seed as an edible part. Its food notes discuss fresh, roasted and baked macadamias in general. Those broad notes give little species-specific guidance on food preparation. The source reports no known hazards and no known medicinal uses. This does not establish safety for every person or pet. Its other-use notes also rely partly on related species. They should not serve as firm claims for this tree. Fresh ripe seed is the stated means of propagation. The source recommends nursery sowing and reports quick germination at 25°C. It lists no weed potential, but provides no pest or disease details.