Oceaniopteris cartilaginea (hammock fern)

Oceaniopteris spp.

Australasia and the southwestern Pacific

SunPart Shade – Full Shade

HardinessZones 9–11

Overview

Oceaniopteris spp. is a genus of terrestrial ferns in the family Blechnaceae, segregated from the larger genus Blechnum spp. and distributed through Australia, New Zealand, New Guinea, and islands of the southwestern Pacific. The genus includes around a dozen species, several of which develop a short, erect rhizome or slender trunk to 1 m (3.3 ft), giving them the look of small tree ferns. Fronds are once-pinnate, leathery, and arranged in a spreading rosette, ranging from 0.3 to 1.5 m (1-5 ft) long depending on species, with closely spaced pinnae that are widest at the base. As in many Blechnaceae, the fronds are dimorphic: fertile fronds stand more erect and bear narrow pinnae with linear sori running along each side of the midrib, while sterile fronds are broader and more spreading. New growth is often flushed pink to bronze before hardening to deep green. Species occur in moist forest, streamsides, and sheltered gullies, and most are frost-sensitive. The genus is closely tied to humid, shaded habitats, and species differ in cold tolerance, with some Tasmanian and New Zealand forms enduring light frost while subtropical species do not.

Native Range

Oceaniopteris spp. ranges across Australia, New Zealand, New Guinea, and the islands of the southwestern Pacific, growing in moist forest, along streams, and in sheltered gullies.

Suggested Uses

Oceaniopteris spp. species are grown in shaded, humid gardens, fern houses, and conservatories in mild climates, and as understory plantings beside streams and ponds. Trunked species are used as small structural ferns in subtropical and warm-temperate gardens.

How to Identify

Plants form a spreading rosette of once-pinnate, leathery fronds 0.3-1.5 m (1-5 ft) long, sometimes raised on a short trunk to 1 m (3.3 ft). The fronds are dimorphic, with narrower erect fertile fronds bearing linear sori along the midrib and broader spreading sterile fronds; new fronds often emerge pink to bronze.

Appearance

Size & Dimensions

Height1' - 5'

Width/Spread1'6" - 5'

Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Oceaniopteris spp., like all ferns, does not flower. Reproduction is by spores borne in linear sori along the undersides of the fertile fronds, released mainly in the warmer months.

Detailed Descriptions

Foliage Description

deep green, flushed pink to bronze when young

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Shade

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.0 - 6.5(Acidic)

357912

Soil Types

loam peat

Drainagemoist

Water & Climate

Water Needs

High

Frost Tolerance

tender

Care & Maintenance

Care Guide

Most Oceaniopteris spp. species grow in humid, shaded to partly shaded positions in moist, free-draining soil rich in organic matter, with a slightly acidic pH of about 5.0-6.5. Consistent moisture and high humidity suit the genus, though established plants tolerate short dry spells in shade. Most species are frost-sensitive and are limited to frost-free or near-frost-free climates, while a few Tasmanian and New Zealand forms withstand light frost. Shelter from drying wind reduces browning of the fronds. Old or damaged fronds can be removed at the base as new growth appears.

Pruning

Pruning is limited to removing old, damaged, or frost-burned fronds at the base in spring as new croziers unfurl. Cutting into the crown damages the growing point, which does not regenerate.

✓ Toxicity

Non-toxic

Fern