Tongue Fern (Pyrrosia lingua): Leathery, Strap-Shaped Epiphyte for Mounts

Overview

Tongue fern (Pyrrosia lingua), also called Japanese felt fern or Shi Wei, is an epiphytic fern native to East Asia. Its simple, undivided, **strap-shaped fronds** (6–12 inches) are thick, leathery, and covered beneath with a dense, felt-like mat of cinnamon-brown hairs (trichomes)—a key adaptation for water retention. The fronds arise singly from a creeping, scaly rhizome, forming colonies on tree trunks, rocks, and walls.

Distinctive Traits

• Felted Undersides: Cinnamon-brown wool insulates and conserves moisture.
• Leathery Durability: Fronds resist desiccation and last years.
• Traditional Medicine: Used in Chinese herbalism (Shi Wei) for urinary and respiratory ailments.

Culture

Bright, indirect light to partial shade. Epiphytic mount (cork, wood, rock) or loose, airy pot. Keep moist; high humidity. Surprisingly cold-tolerant for an epiphyte—hardy to USDA zone 7b with protection. Excellent on shaded walls or in hanging baskets.

Taxonomic Profile

With its felted tongues and rugged constitution, tongue fern brings texture and tradition to epiphyte displays.