Platycerium
Platycerium alcicorne
round shield staghorn fern
- Latin
- Platycerium alcicorne
- Chinese
- 圓盾鹿角蕨
- Japanese
- アルシコルネ
- English
- round shield staghorn fern
Platycerium alcicorne, the round shield staghorn fern, is the type species of the genus and comes from East Africa and Madagascar. Its shields are round, smooth and hug the board; its narrow, wedge-shaped fertile fronds fork repeatedly. A prolific pupper that tolerates sun, dry air and moderate humidity, it is one of the easiest species. Two forms exist, mainland African and Madagascan.
Care notes
Native habitat
Platycerium alcicorne grows in East Africa (Mozambique, Zimbabwe, Tanzania and neighbours) and on Madagascar, the Comoros and the Seychelles, in seasonally dry woodland and coastal forest, on trunks and often on rock. It is the type species of the genus. A real dry season at home is why this staghorn fern tolerates drought and ordinary room humidity better than most.
Light
It likes light. Shade 30–50% in summer; too little light and the fertile fronds stretch thin while the shields stay flat. Near-full sun is fine in winter.
Water and humidity
Let the mount dry before soaking, every three to five days in summer and weekly or less in winter. It grows at 40–60% humidity. The African form takes more wet than the Madagascan form, which wants a little more air humidity and shelter from wind.
Medium and mounting
A multi-bud species that pups generously and quickly forms a clump. The shields are round, entire and hug the surface, so use a flat board; sphagnum moss opened with bark or coco chips, because it resents a stale, waterlogged root ball.
Temperature and seasons (temperate, indoor)
Ideal 18–30 °C. It summers happily outdoors in bright shade. Below 10 °C growth slows into a semi-rest; reduce water rather than stopping it. Above 15 °C it keeps growing all winter on a bright windowsill.
Common problems
- Thin, stretched fertile fronds: not enough light.
- Soft brown shield edges: too wet, not enough air.
- Scale in winter: common indoors, check the undersides regularly.
- Sold as alcicorne, actually bifurcatum: the name was misapplied to the Australian species for decades, so treat old labels with care.
Collector notes
African vs Madagascan form. The mainland form has round, smooth, waxy, yellow-green shields with almost no hair; the Madagascan form, sold in Taiwan and Japan as vassei, has darker shields with a ridged, wrinkled crown, more stellate hair and finer, more evenly forked fertile fronds. Some authors rank them as var. madagascariense or var. vassei; Kew currently sinks P. vassei into synonymy. Not settled. The name vassei cuts both ways: the type of P. vassei was a cultivated plant from Mozambique, and American sellers mostly use 'Vassei' for the African form, so ask which form is meant.
Alcicorne vs wallichii. Some overseas material attaches the name butterfly to alcicorne; in Taiwan that name belongs to the Asian P. wallichii. Alcicorne is multi-bud, round-shielded, with narrow repeatedly forked fertile fronds and spore patches near the tips of the segments. Wallichii is single-bud, with tall lobed shields that brown out completely in the dry season, broad fan-shaped fertile fronds in three uneven lobes, and two large spore patches in the first sinus.
Alcicorne vs ellisii. Both have rounded, glossy shields and juveniles are hard to separate. P. ellisii holds its fertile fronds upright, broad and wedge-shaped, split only once at the tip, and leaves a gap between shield layers; alcicorne forks two or three times into narrower segments and its shields lie flat on each other.
Mother-plant expression. Judge by how round and flush the shields sit, how evenly the fertile fronds fork, and how tight the clump is.
Propagation. Pups and spores. It is a parent of many hybrids, including several with P. elephantotis and P. madagascariense.
FAQ
What is the difference between the African and Madagascar forms of Platycerium alcicorne?
The African form has round, smooth, waxy, yellow-green shields with almost no hair. The Madagascar form, sometimes sold as vassei, has darker shields with a ridged, wrinkled crown, more stellate hair and finer, more evenly forked fertile fronds. It also wants a little more humidity. Some treat them as two varieties, others as one variable species.
Is Platycerium alcicorne the same as the butterfly staghorn fern?
No. Some overseas material attaches the name butterfly to alcicorne, but in Taiwan and most collector usage that name belongs to the Asian P. wallichii. Alcicorne is multi-bud with round entire shields, narrow repeatedly forked fertile fronds and no dormancy; wallichii is single-bud with tall lobed shields, broad fan-shaped fertile fronds and a full dry-season rest.
How do I tell Platycerium alcicorne from P. bifurcatum?
Alcicorne shields are round with an entire, uncut edge, and its fertile fronds are narrow, repeatedly forked and slightly wavy. Bifurcatum shields lobe shallowly at the top and its fertile fronds fork more deeply and broadly. The name alcicorne was misapplied to the Australian species for decades, so old labels and old books are unreliable.
Does Platycerium alcicorne produce pups?
Yes, generously. It is a multi-bud species and mature plants keep throwing pups until they form a clump. Grow it as a colony or separate a pup once it has a few fronds and its own roots. Spore propagation works as well.
Does Platycerium alcicorne go dormant in winter?
Not truly. Growth slows into a semi-rest below about 10 °C and continues above 15 °C. Reduce watering and keep it out of cold draughts; there is no need to withhold water the way you would for wallichii. In a temperate home it grows all winter on a bright windowsill.
How much light does Platycerium alcicorne need?
More than most species. Shade it 30–50% in summer and give it near-full sun the rest of the year. Too little light is the most common mistake: fertile fronds stretch thin and the shields stay flat. In good light the shields are full and round and the fertile fronds stay short with dense forking.
What is a dwarf Madagascar alcicorne, and how do you tell it from the fine-leaved one?
"Dwarf" here is a trade name, not a single selection: nobody claims to have selected it, and the name is used for plants from several unrelated mother plants, for tissue culture from several sources and even for sporelings. It is usually sold as P. alcicorne dwarf, and in Japan also as "compact". Only two points recur across sellers: the plant is small and compact, and the fertile-frond tips curl, which becomes clear only once it is mature. Long narrow fronds, frequent forking and a darker green are each mentioned by only a few sellers; one Japanese shop says the narrow fronds are simply inherited from the Madagascar form, and one American seller describes shorter, thicker fronds instead. The fine-leaved Madagascar form is narrow-leaved too, and listings often mix the two names; the claim that the fine-leaved one grows to normal size comes from a single source. Young plants are almost impossible to tell apart, so ask whether it is a pup, tissue culture or a sporeling (we found nothing on whether sporelings stay small) and ask to see the mature mother plant. Care is the same as for any alcicorne, except that a dwarf holds less moss and dries faster, so water more often in summer.
Related species
Species often compared with, or mistaken for, this one.