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Calochlaena dubia

common ground fern

Dicksoniaceae Eastern Australia and Pacific

Container Friendly

SunPart Shade – Full Shade

WaterMedium

HardinessZones 8–11

Overview

Calochlaena dubia is an evergreen ground fern that spreads by hairy creeping rhizomes to form open colonies, with fronds rising 1.5-4 feet (0.5-1.2 m) tall and patches widening several feet over time. The fronds are soft-textured, broadly triangular, and two to three times divided into many small segments, pale to mid-green, on slender stalks covered with soft pale hairs near the base. New fronds unroll as the typical fern fiddlehead. The rhizomes run below the surface and send up fronds at intervals, so the plant forms a loose, spreading stand rather than a tight clump. Growth is moderate, with colonies widening 6-12 inches (15-30 cm) a year in suitable conditions. Fronds may brown at the tips in dry or exposed positions and die back in severe drought, regrowing from the rhizome. The species spreads steadily and can move beyond its intended area in moist, fertile ground.

Native Range

Native to eastern Australia, from Queensland through New South Wales and Victoria to Tasmania, and also on some Pacific islands. Grows in open forest, gully slopes, creek banks, and disturbed clearings on moist, well-drained soils from near sea level to about 3,300 feet (1,000 m).

Suggested Uses

Grown as a groundcover and understorey fern in shaded native, woodland, and fern gardens, and along damp banks, spaced 18-36 inches (45-90 cm) apart. The spreading habit suits informal mass plantings and erosion control on shaded slopes. Its rhizomes can spread into nearby beds, limiting use in small, formal spaces.

How to Identify

Recognized by the soft, broadly triangular, finely divided pale green fronds rising singly from a creeping rhizome rather than from a crown, and by the soft pale hairs on the frond stalks. The spreading colony habit separates it from clump-forming ferns. Spore patches sit at the segment margins, partly covered by the curled leaf edge.

Appearance

Size & Dimensions

Height1'6" - 4'

Width/Spread3' - 6'

Reaches mature size in approximately 3 years

Colors

Foliage Colors

green

Fall Foliage Colors

no change

Bloom Information

Ferns reproduce by spores rather than flowers. Spores ripen on the undersides of mature fronds through summer and autumn, mainly December to April in its native range. New fronds unroll in spring and continue through the warmer months.

Detailed Descriptions

Foliage Description

Pale to mid-green

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Shade

Tolerates up to 4 hours of direct sunlight daily

• 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 sand peat

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

2-3 years

Care & Maintenance

Care Guide

Grows in part shade to full shade in moist, well-drained soil rich in organic matter. Water through dry spells to keep the soil from drying out fully; fronds brown and die back in drought but regrow from the rhizome after rain. A mulch of leaf litter keeps the rhizomes cool and moist. The spreading rhizomes can extend beyond the intended area and may need a barrier or edge trimming in small gardens. Few pests affect it, though fronds can scorch in direct afternoon sun.

Pruning

Remove old, browned, or damaged fronds at the base in late winter before new growth unrolls. No other regular pruning is needed. Spreading rhizomes can be cut back at the colony edge to contain the patch.

Pruning Schedule

winter