Cheilanthes sieberi
cloak fern
Australia, New Zealand, and the southwest Pacific
Overview
Cheilanthes sieberi is a small terrestrial fern forming tufts of fronds 4-16 inches (10-40 cm) long from a short, scaly rhizome. Fronds are narrow and 2-3 times divided, with a dark, wiry stipe (stalk) about one-third to one-half the frond length. The blade is triangular to lance-shaped and dull green, made up of small leathery segments rolled under at the margins. The undersides bear brown sporangia along the segment edges, protected by the inrolled margins rather than by a separate covering. Fronds are tough and leathery, allowing the plant to withstand seasonal drying; in extended drought they curl and may die back, regrowing from the rhizome after rain. The fern grows in rock crevices, on dry slopes, and in open woodland, often in shallow soils over rock. All fronds contain thiaminase and related compounds toxic to grazing stock, particularly horses and sheep, causing poisoning when eaten over time. Growth is slow, and established clumps spread gradually by the branching rhizome.
Native Range
Cheilanthes sieberi is native to Australia, where it occurs in all states, and extends to New Zealand, New Caledonia, and parts of southern Asia. It grows in dry sclerophyll woodland, rocky outcrops, and grassland, typically in well-drained shallow soils over granite or sandstone from lowlands to montane elevations.Suggested Uses
Cheilanthes sieberi is grown in rockeries, crevice gardens, and containers with free-draining media, spaced 8-12 inches (20-30 cm) apart. It suits dry-shade and native plantings in regions with hot, dry summers. Its toxicity to livestock limits its use in or near grazing paddocks.How to Identify
Appearance
Size & Dimensions
Height4" - 1'4"
Width/Spread8" - 1'
Bloom Information
As a fern, Cheilanthes sieberi does not flower. It reproduces by spores borne along the frond margins, which ripen mainly from spring through autumn. Spores are released in dry conditions and germinate in moist, shaded crevices.
Detailed Descriptions
Foliage Description
dull greenGrowing Conditions
Sun Requirements
Requires 4-8 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
Care & Maintenance
Care Guide
Cheilanthes sieberi grows in full sun to part shade in sharply drained, gritty or rocky soil and tolerates extended dry periods once established. In cultivation it requires sharp drainage, as waterlogged soil causes rhizome rot. Watering during the growing season keeps the fronds green, while drought stress causes them to curl and brown until rain returns. Plants are slow to establish and do not transplant readily once the rhizome is disturbed. The fronds carry thiaminase and are toxic to horses and sheep that graze them over weeks. Few pests affect it, though scale insects occur on plants grown under glass.Pruning
Pruning is limited to removing dead or browned fronds at the base in late winter before new fronds unfurl. Old fronds left in place shelter the crown but build up as dry litter. No other cutting is needed.Container Growing
✓ Suitable for container growing
Minimum container size: 2 gallons