Cyathea medullaris

How hardy is Cyathea medullaris?

Cyathea medullaris (Black Tree Fern) is considered moderately hardy. It can tolerate light frosts once established, typically handling temperatures down to around -2°C to -3°C without serious damage. However, young plants are more frost-sensitive and may need protection (such as frost cloth or planting in a sheltered spot) during their first few years. Extended periods of freezing temperatures or heavy frosts can damage or kill the fronds, though the trunk and growing point (crown) may survive and resprout if not too badly affected. In general, Mamaku is best suited to mild, frost-free to lightly frosty climates where soils stay moist and it is protected from harsh, drying winds. If you're unsure about the hardiness of Cyathea medullaris in your specific location, it's best to consult with The Plant Company.

Cyathea medullaris for sale

The Plant Company has the best Cyathea medullaris for sale in NZ. Our production nursery specialises in growing amazing plants and our logistics team pack them carefully for our customers. The pricing is competitive and the quality is exceptional. Let us look after your plant needs and impress you with both our products and service!

How to grow Cyathea medullaris (Black Tree Fern)?

To grow Cyathea medullaris (Black Tree Fern), you’ll need to recreate the moist, shaded, and sheltered conditions it thrives in naturally. Choose a spot protected from strong wind and intense sun — dappled light under taller trees is ideal. The soil should be rich in organic matter, well-draining, and consistently moist but not waterlogged. Before planting, enrich the soil with compost or well-rotted manure. When planting, position the fern so the crown sits just above soil level. Water deeply after planting and continue to keep the soil moist, especially during dry periods. Mulching with leaf litter or bark helps retain moisture and mimics its natural forest floor environment. In colder areas, protect young plants from frost with frost cloth or by planting in a very sheltered microclimate. Once established, Cyathea medullaris is relatively low maintenance but benefits from regular watering during dry spells and occasional feeding with a diluted liquid fertilizer to encourage lush growth.

What are the landscape uses for Cyathea medullaris?

Cyathea medullaris (commonly known as Black Tree Fern or Mamaku) is used in landscaping to create a dramatic, tropical, or lush native forest atmosphere. Thanks to its tall black trunk and large, arching fronds, it is often planted as a striking feature plant or architectural focal point in shaded or semi-shaded areas. It is ideal for fern gardens, riparian plantings (along streams and wetlands), and large forest-style plantings where its impressive size can be fully appreciated. Mamaku is also used to soften the edges of paths, ponds, or retaining walls, providing a natural, flowing look. In larger landscapes, it can be mass-planted to form dramatic canopies that offer dappled shade for smaller shade-loving plants beneath. Its grand scale makes it particularly suited to parks, eco-restoration projects, and large private gardens aiming to recreate New Zealand’s native forest environments.

What are the common names for Cyathea medullaris?

The common names for Cyathea medullaris are Black Tree Fern, Mamaku, and sometimes simply Black Fern. In New Zealand, Mamaku is the Māori name and is widely used, especially in reference to its cultural and ecological significance.