Introduction & Discovery

Davallia mariesii is the cold-hardy representative of the footed-fern family, a species that alone among commonly cultivated Davallia ventures beyond the tropics into the cool temperate forests of Japan, Korea, Taiwan, and eastern China. Its range extends from the warm-temperate broadleaved evergreen forests of southern Honshu and Kyushu northward to the cool-temperate mixed woodlands of central Japan and the Korean Peninsula, where winter temperatures routinely fall below minus 10 degrees Celsius and the species survives dormant on mossy rocks and tree trunks with its deciduous fronds fallen and its scaly creeping rhizomes exposed beneath snow or leaf litter. The species was described by William Jackson Hooker's successor at Kew, William Turner Thiselton-Dyer's correspondents among the Japanese collectors, and formally introduced to European cultivation through the efforts of Charles Maries, the English collector for the nursery firm of James Veitch and Sons of Chelsea, who brought living material from Japan in the 1870s. The specific epithet mariesii commemorates this collector, whose travels through Japan and China from 1877 to 1879 produced a substantial introduction of ornamental plants to English horticulture including magnolias, camellias, and this hardy fern. Within Japanese horticultural tradition the species has a longer history, known as shinobu and traditionally woven onto bamboo frames to create hanging ornaments called shinobu-dama or tsuri-shinobu, suspended under eaves during the hot summer months as cooling decoration; this traditional craft persists to the present day and connects the species to centuries of Japanese garden and domestic aesthetics. The plant has also been an important component of Chinese traditional medicine under the name gu sui bu, used for bone fractures and kidney complaints, and contemporary pharmacological research has identified flavonoid compounds with osteogenic activity that partially validate traditional applications. In Western gardens the plant occupies a small but loyal niche among hardy-fern specialists and rock-garden enthusiasts who prize its diminutive scale, refined texture, epiphytic creeping habit, and reliable deciduous cycle. For growers in cool temperate climates where the tropical Davallia species cannot survive outdoors, D. mariesii offers the only practical way to cultivate a furry-footed fern in the open garden, and its seasonal rhythm of spring flush, summer elegance, autumn gold, and winter skeletal rhizomes on bare branches provides a year-round ornamental presence that no other hardy fern can match.

Discovery & Naming

Davallia mariesii was formally described and introduced to Western cultivation in the nineteenth century through the efforts of Charles Maries, an English plant collector employed by the Exeter and Chelsea nursery firm of James Veitch and Sons. Maries travelled extensively through Japan and China from 1877 to 1879, collecting living plants, seeds, and herbarium specimens for the Veitch nursery and for the Royal Botanic Gardens Kew. Among his introductions were Magnolia stellata, Hamamelis mollis, several camellias and viburnums, and the small deciduous Davallia that was subsequently named in his honour. The species had been known to Japanese horticulturists for centuries under the name shinobu and used in the traditional shinobu-dama craft, but formal scientific description and entry into Western botanical literature dates from the 1880s. The type locality is generally cited as central Japan. The genus Davallia itself had been established by James Edward Smith in 1793 based on the Canary Islands Davallia canariensis, with the generic name honouring Edmund Davall, the Swiss-English botanist. Nineteenth-century pteridologists including William Jackson Hooker, John Gilbert Baker, and Karel Bořivoj Presl contributed to the clarification of davallioid taxonomy, and the species has featured consistently in East Asian fern floras from the late nineteenth century onward. Twentieth-century monographic treatments by Richard Eric Holttum, Rodolfo Pichi Sermolli, and colleagues refined generic circumscription within Davalliaceae, and molecular phylogenetic work in the twenty-first century has confirmed the placement of D. mariesii within a well-supported temperate East Asian clade of the genus. Contemporary Japanese floras place the species within Davallia as traditionally circumscribed, though some recent treatments merge or split generic boundaries differently within the family.

Native Range & Distribution Map

Distribution map showing the native range of Davallia mariesii.

Biology & Frond Morphology

Davallia mariesii belongs to the genus Davallia in the family Davalliaceae, producing deciduous in temperate climates, semi-evergreen in the warmest parts of its range. fronds are bipinnate to tripinnate, broadly deltate to ovate-deltate in outline, typically 10 to 25 centimetres long and 7 to 18 centimetres wide at the widest basal zone. stipes are slender, wiry, 5 to 12 centimetres long, pale straw to pale chestnut in colour, with a scattering of narrow scales at the base. the lamina is thin-herbaceous, medium to bright green, becoming golden-yellow and falling in autumn in temperate gardens as day length shortens and frost approaches. ultimate pinnulets are oblong-cuneate, 2 to 5 millimetres long and 1 to 2 millimetres wide, each with a single forking vein terminating at the margin. fronds arise at 1 to 3 centimetre intervals along a slender creeping rhizome densely clothed in pale tan to silvery-brown peltate scales. fronds that unfurl from coiled fiddleheads (croziers). Like all ferns, it reproduces via spores borne on the underside of fertile fronds rather than flowers and seeds, and its life cycle alternates between a dominant sporophyte (the visible plant) and a small, short-lived gametophyte stage.

Reproduction & Propagation

Propagation of Davallia mariesii can be achieved through several methods:

• Spores: Collect ripe spores from the underside of fertile fronds, sow on sterilised peat or peat/perlite mix. Do not cover. Keep humid and in bright indirect light. Prothalli (gametophytes) typically develop in 4–12 weeks, and young sporophytes appear after a further 2–6 months.
• Division: Mature clumps with multiple crowns or creeping rhizomes can be divided in spring as new fronds emerge.
• Rhizome cuttings / offsets: Epiphytic genera (Davallia, Polypodium, Phlebodium) can be propagated from 5–10 cm rhizome segments with at least one frond and visible roots.

Cultivation & Substrate

Successful cultivation of Davallia mariesii depends on matching three conditions to its natural habitat: consistent moisture without waterlogging, a humus-rich yet well-drained substrate, and the correct light level for its frond type — whether dappled woodland shade, bright filtered light, or, for a handful of rock ferns, direct sun.

Common Mistakes to Avoid

Several recurring cultivation errors undermine success with Davallia mariesii. The most common is overwintering indoors in continuously warm conditions above 15 degrees Celsius. The species requires an annual cool rest below 12 degrees Celsius for reliable growth, and plants kept warm year-round lose vigour over three to five seasons and eventually decline. A second common error is alarmed removal of the apparently dying plant in autumn as fronds yellow and fall; this is natural deciduous behaviour and the bare scaly rhizomes are fully alive and will reflush in spring. A third error is winter over-watering of the dormant rhizome, which rots in saturated conditions even at cold temperatures; minimal watering in winter is correct. A fourth error is burying the rhizome at planting or repotting, which suffocates the tissue and initiates rot; the rhizome must always lie on the substrate surface or be mounted on slabs with the upper surface exposed. A fifth error is growing the species in heavy peat-based or soil-based composts that retain moisture excessively; only coarse bark-based epiphytic mixes are appropriate. A sixth error is attempting outdoor cultivation in zones colder than 6b without microclimate protection, or in continental climates with very hot dry summers where the species suffers heat stress regardless of winter cold.

Seasonal Considerations

Spring (March to May) is the peak interest period of the cultivation year. Deciduous outdoor plants begin to show swelling frond buds along the rhizomes in late March to April depending on zone and elevation. Remove winter mulch as soon as new growth appears. Apply first quarter-strength liquid feed in mid-April. Watering resumes every three to five days as the substrate begins to dry between natural rainfall events. Best season for repotting, division, and rhizome cuttings. Summer (June to August) is the period of maximum foliar display. Water every three to five days in outdoor plants and as often as daily in container specimens in hot dry weather. Continue fortnightly feeding at quarter to half strength. Monitor for scale insects and spider mites in dry conditions. Sori develop on fertile fronds through midsummer. Autumn (September to November) sees progressive leaf yellowing and abscission beginning in September in colder zones and continuing through November. Reduce watering as fronds yellow; do not feed after early September. Collect spores from mature sori during late August through September. Apply autumn mulch of pine needles, oak leaves, or chopped bark over rhizome zones in late October to early November. Winter (December to February) is the dormant period. Outdoor plants stand as bare scaly rhizomes on their mounts or rocks; water minimally, only enough to prevent complete rhizome desiccation. Protect from prolonged winter-wet saturation with overhead cover if necessary.

Diseases & Pests

Common issues affecting Davallia mariesii in cultivation:

• Root/rhizome rot: Caused by waterlogged substrate, compacted soil, or overwatering in cool weather. Ensure the growing medium is well-aerated and never let pots sit in standing water for prolonged periods.
• Fungal leaf spot & Botrytis: Brown or grey blotches appear in stagnant, overly humid conditions. Improve air circulation, remove affected fronds, and avoid wetting foliage late in the day.
• Scale insects & mealybugs: The most common fern pests, hiding on stipes and frond undersides. Wipe off with a cotton swab dipped in diluted isopropyl alcohol, or treat with horticultural soap. Many chemical pesticides scorch fern fronds — always test on one frond first.
• Spider mites: Fine webbing and stippled fronds, common in dry indoor air. Raise humidity and rinse fronds regularly with tepid water.
• Frond browning (tip burn): Caused by dry air, direct hot sun, fluoridated or chlorinated tap water (especially in Nephrolepis, Calathea-loving filmy ferns), or soluble-salt build-up from fertiliser. Flush the pot with rainwater and reduce feeding.

Indoor Growing & Terrariums

Davallia mariesii can be grown indoors as a houseplant or terrarium subject when its humidity and light requirements are met.

Indoor Setup

• Light: Bright indirect light — an east- or north-facing window, or 30–60 cm under an LED grow light (10–12 hours/day). Most ferns scorch in direct midday sun.
• Humidity: 50–80%. Group plants, stand pots on a pebble-and-water tray, or run a humidifier; misting alone rarely raises ambient humidity enough.
• Temperature: 16–24°C (60–75°F) for most indoor species; avoid cold drafts and hot radiators.
• Substrate: Peat-free potting mix with added perlite and orchid bark for drainage; epiphytic genera (Platycerium, Davallia) grow best mounted on bark or in a bark-heavy orchid mix.
• Water: Keep consistently moist but never waterlogged. Let the top 1–2 cm of substrate dry slightly between waterings in winter.
• Air circulation: A gentle fan discourages fungal leaf spot without drying out the fronds.

Landscape & Garden Use

Davallia mariesii can be used in the garden wherever its hardiness and habitat preferences are matched. Ferns are classic choices for shaded borders, woodland gardens, stumperies, rockeries, stream-side plantings, and ground-cover under trees.

Landscape Tips

• Companions: Hostas, Astilbe, Heuchera, Tiarella, Epimedium, hellebores, snowdrops and other shade-tolerant perennials are classic partners.
• Soil preparation: Incorporate leaf mould or composted bark to improve moisture retention and mimic a forest floor.
• Mulching: A 3–5 cm mulch of chipped bark or leaf litter protects the rhizomes, conserves moisture, and slowly releases nutrients.
• Watering: Establish new plantings with regular deep watering during the first growing season; most hardy ferns need only occasional supplemental irrigation once established.

Conservation & Collector Notes

Davallia mariesii has not received formal assessment on the IUCN Red List and no CITES listing applies. Within its native East Asian range the species is widespread and locally common in suitable habitat across Japan, Korea, Taiwan, and eastern China, and is not considered threatened. However, specific regional population trends reflect broader habitat change: primary forest loss to logging, plantation establishment, and urbanisation has reduced epiphytic fern populations in lower-elevation Japanese and Korean landscapes, while populations in protected mountain areas and shrine groves remain robust. Chinese populations face pressure both from habitat alteration and from collection for traditional medicine use; rhizomes of the species (gu sui bu) are a significant ingredient in traditional Chinese bone-setting and kidney-tonic formulations, and substantial quantities are harvested annually from wild populations in Fujian, Guangdong, and Guangxi for the traditional medicine market. This harvesting pressure is sometimes localised and unsustainable, and in several Chinese provinces concerns about over-collection have prompted research into cultivation alternatives. Plants sold through Western nursery channels are derived from rhizome division or tissue culture of cultivated stock and are not wild-collected. The principal long-term conservation concerns are habitat fragmentation, loss of mature host trees in agroforestry landscapes, and local over-collection for traditional medicine.

Collector Notes

For hardy-fern collectors Davallia mariesii is an essential species, representing the only practical cold-hardy Davallia and the key connection between tropical Davalliaceae and temperate-garden fern collections. Provenance is more meaningful with this species than with most Davallia because populations across Japan, Korea, Taiwan, and mainland China vary in cold tolerance; Japanese and Korean provenances from cooler montane populations are most suitable for temperate European and North American outdoor cultivation, while warmer Ryukyu and Taiwanese provenances may be less hardy. Spore exchange through the American Fern Society, British Pteridological Society, and Japanese specialist societies occasionally offers material of documented origin. Several informal Japanese selections with slightly different frond outline or colour exist in the trade, and cultivated forms with superior hardiness have been selected by specialist Japanese and Korean nurseries. Notable cultivated specimens are held at the Royal Botanic Garden Edinburgh, the Royal Botanic Gardens Kew hardy fern beds, the Tokyo Imperial Palace gardens, and the University of Tokyo Koishikawa Botanical Garden. The species is a favoured subject for shinobu-dama and kusamono work, and specialist Japanese craftspeople maintain breeding stock selected for pliable long rhizomes suitable for weaving onto frames.

Ethnobotany & Cultural Significance

Davallia mariesii holds an unusual dual cultural significance, serving both as a traditional Chinese medicinal herb of long standing and as the subject of a distinctive Japanese horticultural craft tradition. In traditional Chinese medicine the dried rhizomes of the species are the source of the crude drug known as gu sui bu, literally bone-knitting complement, which has been used for at least a thousand years in formulations addressing bone fractures, osteoporosis, kidney deficiency syndromes, tinnitus, and tooth complaints. The rhizomes are classically prepared by cleaning, drying, and sometimes stir-frying or decocting; the material is often powdered for inclusion in compound prescriptions. Modern phytochemical investigation of the species has identified flavonoid glycosides, naringin and related compounds, with documented osteogenic activity in cell-culture and animal models, providing partial scientific validation of traditional applications. Gu sui bu preparations remain in active use across the Chinese-speaking world and are available through traditional medicine dispensaries globally. In Japan the species occupies a quite different cultural position as the source material for shinobu-dama (literally shinobu balls) and tsuri-shinobu (hanging shinobu), decorative moss-and-fern globes and frames woven onto bamboo or wire armatures with living rhizomes wrapped across their surfaces. These ornaments are traditionally suspended under the eaves of houses during the hot summer months, where a wind-chime often hangs alongside, to provide a visual suggestion of coolness. The craft is centuries old and persists as a specialist horticultural tradition with workshops and displays held annually in Tokyo and other cities.

Frequently Asked Questions