Acrostichum aureum Care Guide
Acrostichum aureum is a robust mangrove fern tolerant of brackish swamps, used as a tall background plant in mangrove paludariums.
Compiled by Aquairi from published sources · Published · Updated
Overview
Acrostichum aureum, the golden leather fern or mangrove fern, is a robust fern of tropical and subtropical coasts. It is notable as one of very few ferns tolerant of saltwater, growing in mangrove swamps, salt marshes and riverbanks. In aquaria it is used as a tall background plant in mangrove paludariums and brackish biotope displays.
Taxonomy
- Family: Pteridaceae
- Genus: Acrostichum
- Scientific name: Acrostichum aureum
- Common synonyms: Golden Leather Fern, Mangrove Fern
Habitat
The fern occurs in tropical and subtropical coastal wetlands worldwide, thriving in mangrove swamps, salt marshes and riverbanks. It tolerates raised salinity and soil inundation, though its spores germinate better in fresh water. Fronds are glossy, broad and pinnate, dark green and leathery, reaching up to about 1.8 m long, with some specimens recorded at 4 m on swamp peripheries. Larger fronds bear brick-red sporangia on the upper pinnae. It is classed Least Concern on the IUCN Red List.
Tank requirements
- Placement: background, emersed growth
- Water type: brackish
- Temperature: 22-30 °C (72-86 °F)
- pH: 7.0-8.5
- GH: 8-22 °dGH
- Lighting: high (tolerates full sun to deep shade)
- CO2: not required
- Mature height: up to about 200 cm
Growth and propagation
This is a medium-growing, fast-regenerating fern propagated by division of the rhizome (and naturally by spores). It is rated advanced because of its size and brackish requirements, and grows vigorously in disturbed mangrove areas in the wild.
Propagating Acrostichum aureum (Golden Leather / Mangrove Fern)
Overview
Acrostichum aureum, the golden leather or mangrove fern, is a robust fern whose glossy, leathery pinnate fronds reach about 1.8 m and occasionally 4 m in ideal conditions. The pinnae are dark green and widely spaced; on fertile fronds the upper five to eight pairs bear brick-red sporangia with a felted look. It inhabits mangrove swamps, salt marshes and river banks.
Propagation Method
Two routes work: rhizome division and spores. Division splits an established clump into rooted rhizome sections for fast, true-to-type plants. Spores from the brick-red fertile pinnae can be sown, but spore germination performs better in fresh water than in brackish conditions.
Step-by-Step
- Lift or expose an established clump, keeping the rhizome and roots wet.
- Cut the rhizome into sections, each with roots and at least one frond or growing point.
- Replant divisions into constantly wet substrate such as garden soil or potting mix.
- For spores, collect fertile pinnae bearing brick-red sporangia and sow onto damp substrate in fresh water.
- Grow young ferns on in high light and only then acclimatise them to brackish conditions.
Conditions for Healthy Growth
Give it a constantly wet substrate and high light; it grows well in full sun or even deep shade. Fresh water is adequate for cultivation, while in nature it tolerates brackish, saline swamp conditions. It is fast-growing and regenerates easily, vigorous in disturbed mangrove ground.
Maintenance
Remove old or damaged fronds to keep the clump healthy and make room for new growth. Given its size, divide crowded rhizomes periodically to manage spread and produce new plants. Because it regenerates readily, recovery after trimming or division is usually quick.
Common Challenges
- Poor spore germination if sown in brackish rather than fresh water.
- Substrate drying out, when this fern needs constantly wet ground.
- Underestimating its size; fronds can reach 1.8 m or more and need space.
- Trying to grow it submerged, when it is an emergent marginal species.