Platycerium
Platycerium superbum
moosehorn fern
- Latin
- Platycerium superbum
- Chinese
- 巨大鹿角蕨
- Japanese
- スパーバム
- English
- moosehorn fern
Platycerium superbum, the moosehorn or giant staghorn fern, is an eastern Australian epiphyte whose crown-lobed shield fronds can reach a metre across. Each pendent fertile frond carries a single spore patch in its first fork, which is the one reliable way to separate it from P. grande. It never pups and is grown only from spores.
Care notes
Native habitat
Platycerium superbum grows in and around rainforest in Queensland and north-eastern New South Wales, high on trunks and occasionally on rock. Some references extend the range to New Guinea and Malaysia; that is not settled. The home climate is cool, misty and has a wide day-night swing, which explains why this staghorn fern sulks in hot, still rooms.
Light
Bright, filtered light. Screen midday sun more heavily than you would for P. bifurcatum; scorched shield margins are the first sign. Give it more light in winter when the sun is weak.
Water and humidity
The shields form a large nest that traps litter and holds water. Let the mount dry between soakings, roughly weekly in summer and every two to three weeks in winter. Aim for 60–80% humidity with a fan running; water standing in the nest is how you lose the crown.
Medium and mounting
Temperature and seasons (temperate, indoor)
Ideal 15–27 °C. In a temperate home it is an indoor plant in winter and can summer outside in shade. Hold it above 10 °C; established plants tolerate brief dips to about 5 °C, sporelings do not. It grows slowly indoors, so do not push it with fertiliser in low light.
Common problems
- No growth all summer: heat dormancy, cut water and wait for autumn.
- Brown shield margins: too much sun or dry air.
- Years without fertile fronds: normal, the shield has to reach size first.
- Bought as superbum, turned out to be grande: see below.
Collector notes
Superbum vs grande. Juveniles are near-identical; wait for fertile fronds. P. superbum carries a single spore patch per fertile frond, sitting in the sinus of the first fork, and the frond splits into two main lobes. P. grande carries two patches, one on each side at the second fork, with four main lobes. On the shields, superbum loses its white hair with age and lobes more shallowly; grande stays felted and cuts deeper. Trade mislabelling is common, so ask about the fertile fronds before you buy.
Mother-plant expression. Judge by a symmetrical crown of shield lobes, a full nest and the sweep of the pendent fertile fronds.
FAQ
How do I tell Platycerium superbum from P. grande?
Count the spore patches. Superbum has one per fertile frond, in the first fork, and the frond splits into two main lobes. Grande has two, at the second fork, with four main lobes. Superbum's shields lose their white hair with age and lobe shallowly; grande stays felted and cuts deeper. Juveniles cannot be separated.
Does Platycerium superbum produce pups?
It is generally regarded as a non-pupping species that grows as a single crown, so it cannot be divided. Plants on the market are spore-grown or tissue-cultured. Sporelings vary in crown shape; ask the seller how the plant was propagated and what the mother plant looked like.
Why does my Platycerium superbum stop growing in summer?
It comes from cool, misty Australian rainforest and goes dormant when temperatures sit above about 30 °C. That is normal, not disease. Shade it, run a fan, cut back on water and wait for autumn. In a temperate home this is rarely an issue; in hot climates it is the rule.
How long before Platycerium superbum grows fertile fronds?
Not until the shield has reached a good size. Two to three years from a small sporeling is typical in warm climates, faster where nights are cool. A plant without fertile fronds is not a plant in trouble, provided each new shield is larger and better lobed than the last.
How cold can Platycerium superbum tolerate?
Treat 10 °C as the floor. Established plants ride out brief dips to about 5 °C, but cold combined with wet damages the shields. Keep it out of cold draughts and reduce watering in winter; sporelings and freshly mounted plants come indoors. It is generally rated hardier than grande and less hardy than bifurcatum.
Currently available
Plants of this species you can take home now.