Platycerium
Platycerium holttumii
Holttum's staghorn fern
- Latin
- Platycerium holttumii
- Chinese
- 何其美鹿角蕨
- Japanese
- ホルタミー
- English
- Holttum's staghorn fern
Platycerium holttumii, Holttum's staghorn fern, is a large single-crown species from lowland monsoon forest in Thailand, Laos, Cambodia, Vietnam and northern Peninsular Malaysia. Its tall shield fronds are deeply cut at the top, and its thick fertile fronds project forward with one short erect lobe and one long hanging lobe. It never pups and is the species most often mislabelled as P. wandae.
Care notes
Native habitat
Platycerium holttumii grows on tree trunks in lowland monsoon forest across Thailand, Laos, Cambodia, southern Vietnam and northern Peninsular Malaysia; some records extend it into southwest China. The habitat has a real dry season, which is why this staghorn fern tolerates a full dry-down better than P. wandae does.
Light
Bright, filtered light with some morning sun. Good light is what produces deeply cut shield lobes and thick, stiff fertile fronds. Shade it from midday sun behind glass; a scorched shield keeps its brown scar for years.
Water and humidity
Soak when the surface of the medium is dry. Once the shields have wrapped the board, the core stays damp long after the surface dries, so wait longer than you think. Aim for 60–80% humidity with constant air movement. In still, humid air the thick base of the fertile frond is the first thing to rot.
Medium and mounting
Temperature and seasons (temperate, indoor)
Ideal range 20–32 °C. Indoors year-round in a temperate climate. Keep it above 12 °C; below 10 °C the bud and the newest fronds are damaged. Winter means less water, as much light as you can give it, and a fan running against dry heated air.
Common problems
- Slow as a juvenile: normal. Holttumii lags well behind wandae for its first years, then accelerates.
- Distorted or spotted new fronds: growers report sensitivity to sprays. Test one frond first.
- Cracked, dry shield edges: humidity too low.
- Looks exactly like wandae: see below.
Collector notes
Holttumii vs wandae. On mature plants check three things. First, the bud: wandae has a frill of lacerated tissue around the growing point; holttumii does not. Second, the fertile fronds: both carry one short erect lobe and one long hanging lobe, but in holttumii the erect lobe forks again, while in wandae it stays entire. Holttumii fronds are also thicker, with heavy veins, and project forward rather than drooping. Third, the shields: holttumii holds its stellate hairs longer and reads whiter. Juveniles are near-identical; only provenance separates them.
Mother-plant expression. Look for deep, even lobing at the top of the shield and fertile fronds that are symmetrical, thick and stiff.
FAQ
How do I tell Platycerium holttumii from P. wandae?
On mature plants: wandae has a frill of lacerated tissue around the bud, holttumii does not; the short erect lobe of a holttumii fertile frond forks again and the frond is thick, heavily veined and held forward, while wandae's stays entire and hangs; holttumii shields keep their hairs and look whiter. Juveniles are indistinguishable.
Does Platycerium holttumii produce pups?
No. Like wandae, grande and superbum it grows as a single crown and cannot be divided. Every plant in trade was raised from spores or tissue culture, so ask the seller about the mother plant and the propagation method before you buy.
Why is my Platycerium holttumii growing so slowly?
Juvenile holttumii is naturally slow, noticeably slower than a wandae of the same age. It is a trait of the species, not a care failure. Give it bright light, an airy medium and winter warmth; once the shields start wrapping the board, growth picks up markedly.
How cold can Platycerium holttumii tolerate?
Treat 12 °C as the floor and keep it warmer if you can. Below 10 °C the bud and youngest fronds are damaged. In temperate climates grow it indoors year-round, reduce watering in winter, keep the light high and move it away from cold glass.
How big does Platycerium holttumii get?
In habitat the shield fronds approach a metre across and the fertile fronds pass a metre in length. Cultivated plants run a little smaller but it remains a large species, so plan the board and the wall fixing for the mature plant from day one; remounting later is rarely possible.