Macadamia Nut Tree

Macadamia nut is a broadleaf evergreen tree grown for glossy foliage, fragrant flower clusters, and edible nuts. It is native to eastern Australia and is best suited to frost-free or nearly frost-free climates. ## Site and Seasonal Character The tree develops a broad canopy with whorled, leathery leaves and drooping racemes of pinkish-white flowers, reported in winter and spring. Green husks mature around the hard, smooth shells. North Carolina State Extension gives a cultivated size range of about 30–50 feet tall and 20–40 feet wide, so allow ample room before planting. Choose a sunny, wind-sheltered site with moist, humus-rich soil that drains well. Young trees need regular water while establishing; mature trees tolerate some drought, but irrigation needs still depend on rainfall and soil. The species is frost-sensitive and is listed for USDA zones 9a–12b. In colder locations, growing it in a container that can be protected in winter may be more practical than planting it outdoors. Macadamia nuts are edible for people, but the extension source warns that ingesting parts of the tree can cause serious symptoms in dogs. Keep fallen nuts and plant material away from dogs. For botanical and cultivation details, see the [NC State Extension Plant Toolbox](https://plants.ces.ncsu.edu/plants/macadamia-integrifolia/). ## Maintenance Water deeply and consistently through establishment, and check moisture more often during warm, dry weather. Keep the root zone mulched without piling material against the trunk. Prune only to remove damaged or crossing branches and preserve clearance; protect the tree from strong winds and frost. Harvest mature nuts as they fall, then remove fallen husks and debris from paths.