Hard Fern

Botanical name: Austroblechnum durum
Synonyms: Blechnum durum, Lomaria dura
Common name(s): Hard Fern, Leather Fern

About:
A robust southern New Zealand fern distinguished by its thick leathery fronds and neat symmetrical rosettes. This hardy coastal and maritime species is adapted to cold southern climates, salt spray, and permanently moist environments.

Natural habitat:
Occurs naturally in southern coastal forests, maritime scrub, peat margins, damp rocky slopes, cliff bases, and humid forest understories.

Growing environment:
Partial shade to filtered light, Cool climates, Moist free-draining soils & Salt tolerant.
Thrives in humid southern environments with reliable moisture and protection from prolonged heat.

Endemic distribution:
Endemic to New Zealand.
Occurs mainly from South Westland and Haast through southern South Island forests, Stewart Island/Rakiura, and associated southern coastal regions.

Height:
Approximately 0.3–0.6 m tall

Width:
Forms dense rosettes approximately 0.4–0.8 m across

Flowering:
Not applicable — spore producing fern

Fruiting:
Not applicable — reproduces via spores

Uses:

• Coastal native gardens
• Southern maritime plantings
• Shaded ferneries
• Moist woodland gardens
• Structural foliage planting
• Container growing

Appearance:

Growth habit:
A stout tufted fern forming compact symmetrical rosettes from a short erect rhizome.

Leaves:
Sterile fronds are thick, leathery, dark green, and strongly structured with rounded blunt pinnae.

Fertile fronds:
Fertile fronds are narrower and more erect, arising centrally within the rosette.

Rhizome:
Short erect rhizome clothed in ovate-lanceolate scales.

Ecology:
An important southern coastal fern contributing to understory structure, moisture retention, and habitat stability within maritime forest ecosystems.

Associated habitats:
Frequently associated with southern podocarp forests, coastal shrublands, damp cliff systems, peat margins, and maritime forest understories.

How to grow:
Best planted in cool moist positions with rich organic soil and good drainage. Performs especially well in humid coastal climates and shaded sheltered gardens.

Propagation:
Can be propagated from spores or by division of established rhizomes, though growth is generally slow to moderate.

Garden value:
A bold and highly architectural native fern valued for its rigid leathery foliage and symmetrical habit. Particularly effective in coastal landscapes, southern-style native plantings, shaded courtyards, and cool-climate ferneries.