Delta Maidenhair Fern care guide
Adiantum raddianum · Pteridaceae
Delta Maidenhair Fern (Adiantum raddianum) is a terrarium plant. It belongs to the Pteridaceae family. It is native to Tropical America and the West Indies (Mexico to Argentina and Brazil); clump-forming fern of shaded, humid sites. It needs bright indirect light or partial shade; sun burns the fronds, deep shade weakens it light. Water temperature: 15°C – 21°C. Care difficulty: Demanding. Growth rate: moderate.
How do you care for Delta Maidenhair Fern?
| Light | Bright indirect light or partial shade; sun burns the fronds, deep shade weakens it |
|---|---|
| CO₂ | High humidity (no figure in sources); still needs some air exchange |
| Temperature | 15°C – 21°C |
| Placement | SUITS medium-to-large closed terrariums – steady humidity fixes its biggest houseplant problem. Still fussy, and it needs some air exchange to avoid mould. Split off small divisions to fit; use it midground or background. |
| Growth | Moderate |
| Difficulty | Demanding |
| Family | Pteridaceae |
How do you trim and propagate Delta Maidenhair Fern?
Cut dead or browned fronds at the base. Divide the rhizome in early spring, or sow spores at about 21°C. Keep the crown at soil level.
What problems affect Delta Maidenhair Fern?
Brown, crispy frond tips from low humidity or a dried-out root ball; grey mould on fronds from standing water and poor air movement; scale and mealybugs.
How do you fix Delta Maidenhair Fern problems?
Never let the root ball dry out; water freely in growth, sparingly in winter; avoid water sitting on the foliage. Moist but draining compost, neutral to slightly alkaline. Half-strength liquid feed monthly from mid-spring to late summer. Keep away from draughts and radiators; minimum about 10°C.
Where does Delta Maidenhair Fern come from?
Tropical America and the West Indies (Mexico to Argentina and Brazil); clump-forming fern of shaded, humid sites
What should you know before buying Delta Maidenhair Fern?
Not on the ASPCA toxic/non-toxic list (no toxicity data in the sources used). Widely naturalised outside its native range, including parts of Europe, Africa and Asia.
Sources
- Adiantum raddianum C.Presl (GBIF backbone; distribution from WCVP/Kew) — GBIF / Kew World Checklist of Vascular Plants
- Adiantum raddianum - delta maidenhair fern — Royal Horticultural Society
- Adiantum raddianum — NC State Extension Gardener Plant Toolbox
- Fantastic Terrarium Ferns — Terrarium Tribe
- Toxic and Non-Toxic Plant List - Cats — ASPCA Animal Poison Control Center
Care details checked against these sources on 2026-09-23.
Which aquascapes and tanks use Delta Maidenhair Fern?
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