Davallia tyermanii

A silver-rhizomed fern from subtropical Asian forests

Davallia tyermanii is native to northern Myanmar, southern and southeastern China, and Taiwan. It is an epiphytic or rock-dwelling fern, with creeping rhizomes densely covered in pale scales.

In subtropical forest the rhizomes travel across bark, mossy rock and other exposed surfaces. They grip small pockets of organic material and send fine roots into cracks, while divided fronds rise into humid, moving air. Rain wets the host surface quickly, and moisture then drains away as the forest canopy filters the strongest sunlight.

Indoor care for Davallia tyermanii

Filtered light for blue-green fronds

Place White Rabbit’s Foot Fern close to an east or north-east window, or 0.5–1.5 m back from a brighter south or west exposure. Strong filtered light and a little morning sun keep fronds compact and the surface rhizomes active. Hot midday rays can scorch the fine leaflets and overheat exposed rhizomes; low light creates long, weak fronds and slows the growth that covers the pot. Rotate a hanging basket gradually so light reaches all sides.

Watering roots without soaking the furry surface

Begin watering when the upper 1–2 cm of mix starts to dry while the centre remains lightly moist. Soak the root zone and let the pot drain fully. Keep the furry creeping rhizomes on the surface, where they can dry promptly after watering; do not bury or submerge them and do not leave water trapped around them. A brief surface dry interval is acceptable, but prolonged drying of the fine roots crisps the fronds and shrivels the exposed rhizomes.

A loose fern mix beneath creeping rabbit feet

Use a very airy epiphytic-fern mix of fine bark, coir or a little sphagnum, with perlite or pumice and a modest amount of quality potting substrate. The open mix should hold some moisture around the roots without becoming dense. Keep every furry rhizome on top of the mix or attached across the basket surface; never bury it. A shallow pot, slatted basket or mount suits the creeping habit as long as it can be watered reliably. Rinse salts away gently because both the fine roots and rhizome tips are sensitive to deposits.

Warmth for exposed silver rhizomes

Maintain 18–26 °C and keep the plant above about 13–15 °C. Exposed rhizomes cool and dry faster than buried roots, so keep them away from winter glass and cold draughts. Heater air can dry the growing tips before the potting mix needs water. Avoid rapid temperature changes after watering, and let a mounted specimen drain in the same warm room where it grows.

Humid air around fine blue-green fronds

Average humidity can work with careful watering, but 50–70% helps the fronds unfurl fully and keeps exposed rhizome tips growing. Gentle airflow is equally important around the furry surface and within the fine fronds. Do not seal it in still air. Misting alone cannot hydrate the roots and may keep the rhizome hairs damp only at the surface; use consistent room humidity and water the root ball thoroughly.

Feeding new fronds and furry rhizomes

While new fronds and rhizomes are growing, give Davallia tyermanii balanced foliage fertiliser at quarter strength every four to six weeks. Mounted or bark-grown plants receive few nutrients from their substrate and may need small regular doses in warm, bright conditions, including during winter growth. Stop when frond production slows. Avoid pouring concentrated fertiliser onto the furry tips, and rinse with plain low-mineral water often to prevent residue in the open mix.

Moving the fern while leaving rhizomes exposed

Repot or remount when rhizomes have overrun the support, roots fill the basket, the mix has broken down or water passes through without wetting it. Choose a shallow container only 2–4 cm wider, or a larger open mount. Keep connected rhizomes intact where possible and disturb the fine root mat as little as possible. Secure rhizomes on the surface with loose pins or soft ties until new roots attach; never cover a living section.

Frond and rhizome care

Let the furry rhizomes creep over a pot edge or basket; they are the support structure and must not be trimmed merely for neatness. Divide only a healthy section carrying several fronds, rhizome and roots. Cut dead fronds close to their base. Clean live fronds with a gentle shower, never wipe or scrub the furry rhizomes, and hold the container beneath the root ball without gripping the exposed growth.

What the furry rhizomes and fine fronds of Davallia tyermanii are showing

Pale furry feet creep over the pot edge

These are the fern’s surface rhizomes, not mould, roots that need burying or animal fur. Healthy rhizomes are firm beneath their pale covering and naturally travel across the pot. Leave them exposed on the surface. Investigate only sections that become black, hollow, slimy or foul-smelling.

Rhizomes shrivel and the fine fronds crisp together

The exposed feet and delicate fronds have probably dried too far. Check the mix and the rhizome itself, then rehydrate a dry but still firm plant evenly. Keep future moisture steadier without submerging the furry rhizomes. A wet pot with the same symptoms points to failed roots, not thirst.

A buried furry foot turns dark and soft

Davallia rhizomes need air at the surface and can rot when covered deeply or kept constantly saturated. Uncover the foot, cut the affected section back to firm tissue and refresh stale mix around the remaining roots. Act before softness reaches the next growing point along the creeping rhizome.

Rows of brown marks appear beneath mature fronds

Regular brown sori on the underside are normal spore-producing structures. They stay in organised positions and do not make the upper surface wet or yellow. Leave them alone. Irregular insects, sticky residue or spreading lesions do not match sori and should be examined separately.

New fronds stay small after repotting

Disturbance to the fine roots or creeping rhizome can pause growth. Keep the feet on the surface, the mix evenly moist and the plant in filtered light while it re-establishes. Avoid feeding heavily to force fronds. A shrinking or blackening rhizome indicates damage.

Is Davallia tyermanii toxic to pets?

Davallia tyermanii is non-toxic to cats and dogs. Its furry surface rhizomes and finely divided fronds may still attract chewing, and a large amount of plant material can cause mild digestive upset. Discourage repeated nibbling and contact a veterinarian if vomiting or discomfort persists.

Why this fern is called Davallia tyermanii

Davallia honours Edmund Davall, an English-born botanist who worked in Switzerland. James Edward Smith established the fern genus in 1793. Thomas Moore first described this species in Humata, and H. J. Veitch later moved it to Davallia. The accepted spelling is tyermanii, although tyermannii remains common in horticulture.