Platycerium ridleyi

Give it bright, filtered daylight and keep humid air moving around the plant. Choose an airy spot with strong sun softened by a sheer curtain or filtered shade. A grow light can help if daylight is limited.

Keep it warm in winter and protect it from overheating in summer.

A slow-growing solitary fern of wet tropical forest, usually about 0.5–0.6 m across at maturity. Overlapping shields enclose the roots beneath a crown of stiff ascending fronds. It grows on trees in primary, secondary, and freshwater-swamp forest, with documented associations with ants and Lecanopteris ant ferns. It does not normally produce pups.

Rounded to kidney-shaped shields measure about 20–50 cm long and 20–40 cm wide. Strong radiating ribs and raised veins form deep channels. Overlapping shields fold around the host, enclosing a ventilated root chamber often occupied by ants. Mature shields are usually green, although old or damaged tissue can brown.

Stiff, leathery fertile fronds grow upward, reach 25–50 cm or more, and fork repeatedly into antler-like divisions. Each carries a separate oval or elliptical spore-bearing lobe about 5–17 × 3–15 cm. Its spore-bearing surface turns brown as it matures.

Recognize P. ridleyi by its solitary crown, deeply ribbed green shields enclosing the roots, and stiff upright antler fronds with separate oval spore-bearing lobes. P. coronarium forms colonies and has long hanging fronds with rounded or kidney-shaped fertile lobes.

1909

Hermann Christ published the species in 1909, naming it for British botanist Henry Nicholas Ridley, who collected the original material at Bukit Timah, Singapore.