<i>Cyathea cunninghamii</i>(Cyathea cunninghamii) hero image

Slender Tree Fern

Cyathea cunninghamii

Not specified

This native plant, known as Slender Tree Fern(scientific name: Cyathea cunninghamii ), is a remarkable species endemic to New Zealand. It is characterized by its unique features, ecological role, and cultural significance. This comprehensive guide provides detailed information on its care, propagation, and importance within the New Zealand ecosystem. Understanding this plant contributes to the appreciation of our rich biodiversity and heritage, and supports conservation efforts for Browse All .

<i>Cyathea cunninghamii</i>(Cyathea cunninghamii) showing <i>Cyathea cunninghamii</i>growth habit
Image credit: Slender Tree Fern ( Cyathea cunninghamii ) - Photo via Wikipedia

Plant Description

Identification and Physical Characteristics

Cyathea cunninghamii , commonly known as the Gully Tree Fern or Slender Tree Fern, is a tall tree fern native to New Zealand and parts of Australia Discover more aboutNew Zealand. It has a slender, erect trunk that can grow up to 20 meters tall and typically ranges from 3 to 15 cm in diameter, often covered with persistent stipe bases in its upper parts. The fronds are 1.5 to 3 meters long, forming a relatively small crown, and are typically dark green above and paler green below, with a soft texture. They are 3-pinnate (divided three times). The stipes (frond stalks) are short, coarse, black, and dull, with numerous small, sharp tubercles. The sori (clusters of spores) are conspicuous, globose, and arranged in rows on the lower surface of the pinnules, covered by a cup-shaped indusium. This tree fern typically grows along creeks in sheltered coastal fern gullies and damp forest areas, preferring moist environments and having a lower tolerance for drought compared to other tree fern species.

Quick Facts

Cyathea cunninghamii quick facts
Scientific Name Cyathea cunninghamii
Height 10-20 m
Spread 3-5 m
Water Needs High, requires consistently moist soil
Light Full shade to filtered sunlight
Frost Tolerance Low - requires protection from frost
Salt Tolerance Low; requires protection from salt exposure
Growth Rate Slow
Lifespan Long-lived

Climate Best Suited to

Cyathea cunninghamii is well adapted to various New Zealand regions.

Regional Suitability

City suitability for Cyathea cunninghamii
City Climate Suitability
Auckland High
Wellington High
Christchurch Medium

Plant Habitat

Natural Occurrence and Ecology

Understand the highly specialized natural habitat of Gully Tree Fern ( Cyathea cunninghamii ), including its specific geographical distribution, exacting environmental requirements, and the unique gully ecosystems where it thrives. This knowledge is essential for successful cultivation.Specific geographical distribution in cool, wet gullies throughout New Zealand.Specialized microhabitat requirements in protected forest environments.Associated plant communities and typical gully ecosystem companions.

Growing Requirements

Soil Requirements

Prefers well-draining soil rich in organic matter.

  • Well-drained
  • Loamy

Light Requirements

Grows best in partial to full sun.

  • Full Sun
  • Partial Shade

Water Requirements

Requires regular watering during dry periods.

  • Regular
  • Drought tolerant once established

Planting and Establishing

Establishment Guidance

Plant Cyathea cunninghamii in a hole twice the width of the root ball.

Proper establishment is key to long-term success. Ensure the planting hole is twice as wide as the root ball and backfill with a mix of native soil and organic compost. Initial watering should be thorough, followed by regular monitoring during the first two growing seasons to ensure the plant becomes well-anchored and resilient to local climate fluctuations.

Ecological Role

Biodiversity and Ecosystem Impact

Provides habitat and food for native fauna.

This species plays a vital role in its local ecosystem, providing essential habitat and food sources for native biodiversity. Its presence supports complex ecological interactions, contributing to the overall health and stability of the environment. By planting this native, you help maintain the intricate web of life that defines New Zealand's unique natural heritage.

Uses & Significance

Garden Uses

Ideal for rock gardens and native borders.

  • Rock gardens
  • Ground cover

Ecological Value

Supports local pollinators.

  • Birds
  • Insects

The versatility of this plant makes it a valuable addition to many New Zealand gardens. Beyond its aesthetic appeal, it offers practical benefits such as soil stabilization and shelter for smaller plants. Its historical and modern uses highlight its enduring importance in both traditional practices and contemporary landscape design, making it a thoughtful choice for any restoration or gardening project.

Landscaping Uses

Adds texture and form to modern landscapes.

In a landscape setting, this plant provides excellent structure and year-round interest. Its unique form and foliage can be used to create focal points or as a cohesive element in a larger native planting scheme. It pairs well with other New Zealand natives, allowing for the creation of diverse and resilient garden environments that reflect the natural beauty of Aotearoa.

Seasonal Care Calendar

Spring

Mulch and apply balanced fertilizer.

  • Fertilize
  • Mulch

Summer

Water deeply during dry spells.

  • Water
  • Check for pests

Autumn

Tidy up any dead foliage.

  • Prune lightly
  • Plant new specimens

Winter

Protect from heavy frosts if necessary.

  • Frost protection

When to Prune and How Much

Minimal pruning required to maintain shape.

  • Remove dead branches

Always use clean, sharp tools.

Regular maintenance through careful pruning ensures the plant remains healthy and maintains its desired shape. Focus on removing dead or diseased wood to promote better air circulation and prevent the spread of pathogens. Proper pruning techniques help the plant direct its energy toward new growth, resulting in a more robust and aesthetically pleasing specimen in your garden.

How to Grow Slender Tree Fern

Cultivating Cyathea cunninghamii ( Cyathea cunninghamii ) is a rewarding endeavor for any gardener interested in New Zealand's unique flora. This species can be propagated through several methods, each requiring specific conditions to ensure healthy growth and establishment. Successful propagation depends on mimicking the plant's natural environment and providing consistent care during the early stages of development.

From Seed

Propagation from seed is often the most effective way to produce a large number of Cyathea Cunninghamii plants. Seeds should be collected when they are fully mature. Freshly collected seeds generally have higher germination rates than those that have been stored for long periods.

Sow fresh seeds in a seed-raising mix.

  1. Collect seeds
  2. Sow in trays

Keep moist until germination.

From Cuttings

For those wishing to replicate specific characteristics of a parent plant, vegetative propagation via cuttings is the preferred method. This technique ensures that the new plants are genetically identical to the source. Semi-hardwood cuttings taken during the appropriate season usually yield the best results for this species.

Take semi-hardwood cuttings in late summer.

  1. Take cuttings
  2. Use rooting hormone

Additional Methods

Depending on the growth habit of Cyathea cunninghamii , other methods such as division or layering might also be viable options. Division is particularly suitable for plants that form dense clumps or have spreading root systems, while layering can be used for species with trailing or flexible stems.

Division can be done in early spring.

  1. Divide clumps
  2. Replant immediately

Pests & Diseases

Generally resistant to major pests.

While generally resilient, maintaining optimal growing conditions is the best defense against pests and diseases. Regular monitoring allows for early detection of any issues, which can often be managed through cultural practices or organic interventions. Ensuring good air circulation and appropriate watering will significantly reduce the plant's susceptibility to common environmental stresses and pathogens.

Cultural Significance

Cyathea cunninghamii , also known as the slender tree fern or gully tree fern, holds cultural significance for both Aboriginal peoples in Australia and Māori in New Zealand, primarily through traditional medicinal uses and its place in naming conventions.Traditionally used for its medicinal properties. An infusion and decoction made from the entire plant, often combined with other species, is used to treat eye inflammation, including conjunctiva and purulent ophthalmia.The plant, when mashed, is applied externally to alleviate conditions such as rheumatism, swellings, headaches, colds, ulcers, and open sores.The seeds of Cyathea cunninghamii are consumed to help relieve fever and diarrhea.Known by the Māori common names "Ponga" and "Pūnui".While general traditional Māori uses for tree ferns, such as the consumption of stems and roots for food, have been noted, specific cultural practices directly linked to Cyathea cunninghamii beyond its naming are not extensively detailed in available information.Some sources suggest that the pulp of juvenile fronds from "Ponga Fern" (which may refer to Cyathea cunninghamii in a broader sense) possesses healing properties and is utilized in skincare for its toning and tightening effects.

  • Traditional medicine
  • Crafts

Bonus Tip

Excellent for low-maintenance gardens.

For an extra boost, consider applying a thin layer of high-quality organic mulch around the base of the plant. This helps retain soil moisture, suppresses weeds, and gradually improves soil structure as it breaks down. This simple step can make a significant difference in the plant's overall vigor and resilience, especially during periods of extreme weather.

Plant Conservation

Conservation Status

The conservation status of Cyathea cunninghamii , also known as the Slender Tree-fern or gully tree fern, varies by region and assessment.Victoria:Listed as "Critically Endangered" under the Flora and Fauna Guarantee Act 1988 and was categorized as "Vulnerable" in the 2014 Advisory list of rare or threatened flora. The projected population reduction over the next 75 to 100 years is estimated to be 60 to 75% due to climate change and ongoing threats. Historically, population reduction over the past 75 to 300 years is inferred to be 50 to 85% due to timber harvesting and unsuitable fire regimes.Tasmania:Listed as "Endangered" under the Threatened Species Protection Act 1995.In New Zealand it is generally considered uncommon and slow‑growing, preferring damp forest environments, often in stream gullies and riverbanks. It has a lower tolerance for drought compared to other related species.Threats include habitat loss, altered fire regimes, and the impact of climate change.