Asplenium trichomanes aka Maidenhair Spleenwort

Asplenium trichomanes is a small fern called maidenhair spleenwort. It belongs to the spleenwort family, Aspleniaceae. Its range spans much of the world's temperate regions. It also grows in mountains within the tropics. It is native to Britain and Ireland. Wild plants grow on shaded cliffs, rocky slopes, and scree. They also root in cracks in rocks and walls.

This evergreen fern forms small clumps from a stout rhizome. Its roots stay close to the surface. Garden plants stand about 0.5–0.7 feet [0.15–0.2 metres] tall. Small colonies can spread to 1 foot [0.3 metres] across. Some accounts report fronds reaching 1 foot [0.3 metres] long. RHS gives broader height and spread bands, reaching 1.6 feet [0.5 metres]. The dark green fronds form a tight rosette. Each pinnate frond carries small, round or oblong leaflets. The glossy leaf stalk is dark brown to almost black. Fronds stand upright or bend in a gentle arch. Offsets let the plant spread slowly into small groups.

This fern has no flowers or fruit. It reproduces through spores rather than seeds. Gardeners can also divide plants in spring. It grows best in partial or full shade. Give it soil rich in humus that drains well. Keep the soil moist without letting water collect around roots. RHS suggests adding grit to improve drainage. A humid, sheltered site suits it well. It can grow in shallow soil among rocks. Missouri Botanical Garden lists USDA zones 5–8. NC State gives a wider range of zones 3–9. RHS rates its winter hardiness as H6.

Its small size suits shaded walls, rock gardens, and pots. It also fits moss gardens and the edges of beds. Planting spaces on the north side of walls suit it. Under good conditions, it can spread and settle into cracks. Established plants need little care. Remove dead or damaged fronds when needed. The cited garden sources report few pest or disease problems.

Dried fronds have served as a substitute for tea. Past herbal use includes chest complaints and promoting menstruation. These reports describe traditional use, not proof of benefit. The sources report no known cases of toxicity for this species. That does not establish that eating it is safe.