How to grow macadamias starts with giving these Australian natives the warm conditions they love. With glossy evergreen foliage and the bonus of delicious homegrown nuts, macadamia trees can become a productive feature in the backyard for many years.
Plant your macadamia tree
Macadamias grow best in subtropical climates and also do well in warm temperate areas. Young trees are frost tender, so give them a sheltered spot in cooler gardens. Choose a position in full sun with protection from strong winds and enough room for the tree to develop. Remember, a mature macadamia can become a substantial tree, so give it plenty of space away from buildings and other large plants.
Spring is a great time to get a young tree established while the soil is warming and there’s a full growing season ahead.
Macadamias prefer fertile, well-drained soil that holds moisture without becoming waterlogged. Before planting, improve the soil with plenty of organic matter if needed.
Dig a hole around twice as wide as the root ball but no deeper. Position your macadamia at the same level it was growing in its pot, backfill gently, firm the soil and water thoroughly.
How to grow macadamias successfully
Young macadamia trees appreciate consistent moisture while their root systems establish. Water deeply and regularly during dry periods, particularly as the weather warms, while allowing excess water to drain away.
Once planted, spread a layer of The Garden Family Sugar Cane Mulch over the soil to help retain moisture, suppress weeds and protect the root zone from temperature extremes. As it gradually breaks down, it also adds organic matter back into the soil. Keep the mulch clear of the trunk to prevent moisture building up against the bark.
Macadamias have a relatively shallow root system, so take care when gardening around the base of the tree. Avoid digging deeply beneath the canopy where you could damage feeder roots.
Keep an eye on young trees during hot and dry weather. Deep watering encourages moisture to move further into the soil, rather than encouraging roots to remain close to the surface.
Macadamia flowers and fruit
One of the highlights of growing a macadamia is seeing it come into flower. Long sprays of small white, cream or pink flowers appear on the branches, attracting pollinators before developing into clusters of nuts.
You’ll need a little patience before enjoying your first homegrown harvest. Young macadamia trees can take several years to begin producing a worthwhile crop, with production increasing as the tree matures. Grafted trees usually start bearing in 4 to 5 years, while seedlings can take much longer. Growing more than one compatible variety nearby may also help with pollination and fruit set.
As the nuts mature, they develop inside a green outer husk. When they’re ready, the husk splits and mature nuts naturally fall from the tree.
Note: Macadamias are toxic to dogs, so collect fallen nuts regularly if you have pets.
When to harvest macadamias
Macadamia harvest time is usually autumn to winter.
Rather than picking nuts directly from the branches, collect mature macadamias after they fall. Check beneath the tree regularly during harvest time and remove the outer husk soon after collecting them.
Inside the husk is the familiar hard shell protecting the macadamia kernel. Freshly harvested nuts need to be properly dried before they’re cracked and eaten. Drying reduces their moisture content and helps develop the crunchy texture and rich flavour macadamias are known for.
Ready to crack into your harvest? Gardening Australia shares some handy tips for cracking macadamia nuts.
With the right conditions, growing macadamias can reward you with homegrown nuts for decades. Give your tree plenty of sunshine, regular moisture and a protected root zone, and in time you could be collecting one of Australia’s favourite nuts from your own backyard.
