Macadamia Nut Tree Care and Growing Guide

Plant Care

Once established, the Macadamia Nut Tree is fairly low maintenance, but it does have some specific needs for warm temperatures, good draining soil, and some patience to grow nuts. Frequent watering and some feeding encourage healthy growth and nut production.

Light

Macadamia trees need full sun to produce well, at least 6-8 hours of direct sunlight each day. Afternoon shade may prevent leaf scorch in hot areas; however, too much shade will reduce flowering and nut yield.

Soil

Macadamia trees also require well-draining, slightly acidic to neutral soil (pH 5.5-7.5). They like loamy or sandy soil with compost, since heavy clay can rot the roots. If your soil holds too much water, mix in sand or perlite to promote drainage.

Watering

Macadamia trees require regular moisture, particularly during the first few years of their life. Rotate the pot every week so the plant grows evenly and water once or twice a week as needed to keep the soil moist but not wet. Once established, trees are somewhat drought-tolerant, but regular watering during flower and nut development will increase yields.

Pruning

Pruning keeps the Macadamia tree compact, productive, and disease-free.

In the early years, prune low-hanging branches to promote vigorous upward growth. Once mature, prune out any dead, damaged or overcrowded branches to permit better air passage. If growing in a small space, occasional height control pruning can keep the tree more manageable.

Once harvested, lightly shape the tree for an open canopy to promote better light penetration and nut production.

Propagation

Macadamia trees can be grown from seed or by grafting, which is faster and more reliable.

• Plant fresh Macadamia nuts in a moist, well-draining mix for seed propagation. It can take months for seeds to germinate, plus seed-grown trees may not produce nuts for 8-12 years.
• Select grafted trees from a nursery for faster fruit production.  Grafted trees typically start producing within 3-5 years and offer better nut quality than seed-grown trees.

Growing in Pots

Although macadamia trees grow large, they can thrive in containers with proper care.

• Use a pot that’s at least 20-24 inches wide and deep to accommodate its root system.
• Fill with a well-draining, slightly acidic potting mix, improved with organic compost.
• Grow in full sun encourages robust growth and flowering.
• Water consistently to keep the soil moist (but not soggy).
• Use a balanced, slow-release fertilizer throughout the growing season.
• Select a dwarf or grafted variety, which works best in a container.

Overwintering

Macadamia trees do not tolerate frost and require protection in cooler regions.

Once night temps descend below 40°F (4°C), take your potted trees inside or into a house. For in-ground trees, cover the root zone with a thick layer of mulch to help insulate the roots. On cold nights, cover young trees with frost cloths or burlap.

In zones below 9, macadamia trees should be grown in large pots and moved to a warm, sheltered area during winter.

Common Issues

Macadamia trees are generally pest-tolerant, but they can face a few issues.

• Nut borers → Small larvae tunnel into nuts, lowering yield. Clean up fallen nuts and apply organic pest controls.
• Root rot → Overwatering or poor drainage. If watering, make sure the soil is well-draining and doesn’t cause waterlogging.
• Leaf spots → In humid conditions, fungal infections can develop. Support air flow and apply fungicidal sprays as needed.
• Low nut production → Often due to lack of sun, poor pollination, or nutrient deficiencies. Improve growing conditions and consider hand-pollinating flowers.

Summary

If you love nuts, try the Macadamia Nut Tree. Awesome, beautiful tree provides shade and fragrant blooms, and delicious homegrown nuts. While it requires patience before producing nuts, its low-maintenance nature and long lifespan make it a valuable addition to any warm-climate garden. Whether planted in the ground or a big pot, this iconic nut tree will provide beauty and bounty for years to come.