Hound's Tongue Fern (Kōwaowao)
Microsorum pustulatum
Microsorum pustulatum, commonly known as Hound's Tongue Fern or Kōwaowao in te reo Māori, is a versatile and adaptable native fern of New Zealand. With its distinctive leathery fronds that resemble a dog's tongue, this epiphytic fern can be found growing on trees, rocks, and occasionally on the ground. Its ability to thrive in various conditions and its attractive, evergreen foliage make it both an important component of native ecosystems and a popular choice for gardens. native trees
Image credit: Kōwaowao (Microsorum pustulatum). Wikipedia
Quick Facts
| Scientific Name | Microsorum pustulatum |
|---|---|
| Height | Fronds up to 60 cm (24 in) long |
| Spread | Forms dense mats, spreading by rhizomes |
| Water Needs | Low to moderate; prefers moist but well-drained soil |
| Light | Partial to full shade; tolerates filtered sunlight |
| Frost Tolerance | Moderate; tolerates light frosts |
| Salt Tolerance | Low; not suited to exposed coastal sites |
| Growth Rate | Moderate |
| Lifespan | Perennial; long-lived in suitable conditions |
Climate Best Suited To
Hound's Tongue Fern is remarkably adaptable and can be found throughout New Zealand in suitable habitats. It thrives in humid, sheltered environments but can tolerate drier conditions once established. Its epiphytic nature allows it to grow in a variety of situations, from coastal forests to mountain slopes.
Regional Suitability
| City | Climate Suitability |
|---|---|
| Whangārei | Ideal |
| Auckland | Ideal |
| Hamilton | Ideal |
| Tauranga | Ideal |
| Rotorua | Ideal |
| Gisborne | Ideal |
| New Plymouth | Ideal |
| Napier | Moderate |
| Whanganui | Ideal |
| Palmerston North | Ideal |
| Wellington | Ideal |
| Nelson | Ideal |
| Christchurch | Moderate |
| Dunedin | Moderate |
| Invercargill | Moderate |
Growing
- Thrives in moist, well-drained soil
- Prefers partial to full shade
- Tolerates dry periods once established
- Good for underplanting in native gardens
Growing Requirements
Soil Requirements
Prefers moist, well-drained soil but tolerates a range of substrates, including tree bark and rocks.
- Thrives in humus-rich, slightly acidic soils
- Can grow as an epiphyte or terrestrial
- Does not tolerate waterlogged conditions
Light Requirements
Best in partial to full shade, mimicking its natural forest habitat.
- Will tolerate filtered sunlight
- Direct sun may scorch fronds
Water Requirements
Low to moderate water needs once established.
- Keep moist during establishment
- Tolerates dry periods but prefers consistent moisture
Uses & Significance
Garden Uses
- Ground cover in shaded gardens
- Epiphytic displays on trees or logs
- Container plant for patios and indoor spaces
- Restoration planting in native bush
Ecological Value
- Provides habitat for invertebrates
- Contributes to forest humidity and microclimate
- Stabilizes soil and prevents erosion
Cultural Significance
Known as kōwaowao or pāraharaha in te reo Māori, this fern was used medicinally and as a food wrap in hāngī. It is a symbol of resilience and adaptability in New Zealand forests.
Learn more about the cultural significance of native plants in Cultural Plants.
Seasonal Care Calendar
Spring
- Remove old fronds and apply mulch
- Watch for new growth
Summer
- Water during dry spells
- Monitor for pests like scale insects
Autumn
- Tidy up fallen fronds
- Divide plants if needed
Winter
- Protect from heavy frost in cold areas
- Minimal care required
Pruning
- Remove dead or damaged fronds as needed
- Minimal pruning required for healthy growth
Planting Guide
- Choose a shaded or semi-shaded site with moist, well-drained soil
- Dig a hole large enough for the root ball
- Plant at the same depth as in the nursery container
- Water well and mulch to retain moisture
Propagation Methods
Division
The most reliable method for home gardeners:
- Identify a mature plant with multiple growing points
- Carefully remove the plant from its substrate
- Gently separate the rhizomes, ensuring each section has fronds and roots
- Replant or mount divisions immediately
- Keep consistently moist until established
- Protect from direct sun and wind until new growth appears
Rhizome Cuttings
An effective method for increasing your collection:
- Select healthy rhizome sections with at least one growth point
- Cut rhizome into 5-10 cm lengths
- Allow cut ends to dry for a few hours
- Place on or slightly embedded in moist sphagnum moss
- Maintain high humidity until new growth appears
- Transplant once new fronds and roots have developed
Spores
For those wanting a challenge:
- Collect fertile fronds when spore cases (sori) turn brown
- Place fronds on clean paper in a warm, dry place for 1-2 days
- Collect the fine, dust-like spores that fall onto the paper
- Prepare a sterile growing medium of peat and perlite
- Sprinkle spores thinly over the surface
- Cover with glass or plastic to maintain humidity
- Keep at 18-21°C (65-70°F) in indirect light
- Mist with distilled water to maintain moisture
- Prothalli will form in 1-3 months
- Young ferns will develop in 6-12 months
- Transplant when several fronds have formed
Cultural History
Hound's Tongue Fern has a significant place in New Zealand's natural and cultural heritage:
Traditional Māori Uses
- Known as "kōwaowao" or "pāraharaha" in te reo Māori
- Used medicinally to treat skin conditions and wounds
- Fronds applied to burns and infections
- Used to wrap food for cooking in earth ovens (hāngī)
- Served as a calendar plant, with new growth indicating seasonal changes
Ecological Significance
- Important epiphyte in native forest ecosystems
- Provides habitat for small invertebrates
- Contributes to forest biodiversity
- Helps retain moisture in forest environments
- Indicator species for healthy forest ecosystems
European Settlement Impact
- Documented by early European botanists
- Habitat reduced through forest clearance
- Included in Victorian-era fern collections
- Specimens sent to European botanical gardens
Contemporary Significance
Today, Hound's Tongue Fern is valued both for its ecological role in native forests and as an ornamental plant in gardens. Its adaptability and distinctive appearance make it popular for both indoor and outdoor cultivation. Conservation efforts include preserving its natural habitat in protected forest areas and using it in restoration projects to rebuild native forest ecosystems.
Pests & Diseases
Common Pests
- Scale Insects: May appear on fronds as small bumps. Remove with cotton swab dipped in alcohol or use horticultural oil.
- Mealybugs: Sometimes infest the crown and base of fronds. Treat with insecticidal soap or neem oil.
- Slugs and Snails: Can damage fronds, especially new growth. Control with organic baits or barriers.
- Spider Mites: May occur in dry conditions. Increase humidity and treat with insecticidal soap if necessary.
Common Diseases
- Rhizome Rot: Caused by overwatering or poor drainage. Ensure well-draining substrate and avoid waterlogged conditions.
- Fungal Leaf Spots: Various fungi can cause spotting on fronds. Improve air circulation and avoid overhead watering.
- Powdery Mildew: May appear as white powder on fronds. Improve air circulation and treat with fungicide if severe.
Environmental Issues
- Desiccation: Low humidity causes frond edges to brown and curl. Increase humidity with misting or grouping plants.
- Sunburn: Direct sunlight causes yellowing and browning of fronds. Move to a more shaded location.
- Frost Damage: Severe frosts can damage fronds. Protect with frost cloth during cold snaps.
- Nutrient Deficiency: Yellowing fronds may indicate lack of nutrients. Apply a diluted organic fertilizer formulated for ferns.
Hound's Tongue Fern is generally resilient to pests and diseases when grown in appropriate conditions. Its leathery fronds are more resistant to damage than many other ferns. Good cultural practices including proper spacing, appropriate watering, and good air circulation will prevent most problems.
Bonus Tip
How to Use Hound's Tongue Fern in Your Garden
Create a stunning living wall display by mounting Hound's Tongue Fern on wooden boards or in vertical planting pockets. Its epiphytic nature makes it perfect for vertical gardening, and the leathery fronds add texture and interest to walls. Combine with other epiphytes like Pyrrosia eleagnifolia (Leather-leaf Fern) and Asplenium flaccidum (Hanging Spleenwort) for a diverse display that mimics natural forest growth patterns. Mist regularly to maintain humidity and ensure the mounting medium stays consistently moist until plants are established.
