Small ferns for terrariums (varieties that actually work)
Not all ferns thrive in jars. The 5 small ferns that actually work, with specific care notes.
Ferns add the height and texture that makes a terrarium feel like a tiny forest. But most ferns are too big, too dry-air-loving, or too delicate. Here’s the small list of ferns that actually work in terrariums.
The 5 winners
1. Button fern (Pellaea rotundifolia)
Round, leathery leaflets on wiry stems. Very forgiving. Tolerates being forgotten.
- Light: Low to medium indirect
- Humidity: 60%+
- Growth: Slow
- Watch out for: Overwatering (rot)
2. Maidenhair fern (Adiantum)
The classic terrarium fern. Delicate, beautiful, dramatic when happy. Also dramatic when unhappy.
- Light: Medium indirect (more light = better color)
- Humidity: 70%+
- Growth: Medium
- Watch out for: Drying out (irreversible crispy leaves)
3. Lemon button fern (Nephrolepis cordifolia ‘Lemon Button’)
Compact Boston fern variety. Slightly citrus-scented. Tolerates more abuse than maidenhair.
- Light: Medium indirect
- Humidity: 60%+
- Growth: Medium
- Watch out for: Outgrowing the jar — trim regularly
4. Holly fern (Cyrtomium falcatum)
Stiff, leathery fronds. Surprisingly tough for a fern.
- Light: Low to medium indirect
- Humidity: 50%+
- Growth: Slow
- Watch out for: Slow start, but worth the wait
5. Rabbit’s foot fern (Davallia fejeensis)
Fuzzy rhizomes that creep over hardscape. Conversation starter.
- Light: Medium indirect
- Humidity: 60%+
- Growth: Medium
- Watch out for: Rhizomes drying out (mist them directly)
General fern care
What all terrarium ferns share
- They HATE drying out
- They LOVE humidity
- They want indirect light
- They sulk dramatically when moved (give them 2 weeks to recover)
- Brown fronds are not always dead — leave them, new growth may emerge
Common problems
Brown crispy edges: Low humidity or dry soil. Fix both. Yellow fronds: Overwatering OR old age. Check soil moisture. No new growth: Plant may be dormant (normal in winter) OR light is too low. Sudden collapse: Usually overwatering or temperature shock.
Pairing ferns with other plants
Great pairings:
- Selaginella (ground cover beneath ferns)
- Cushion moss (around fern base)
- Fittonia (color contrast)
Avoid pairing with: succulents, anything that needs dry conditions.
Where to buy
- Local nurseries (best for inspection)
- Etsy (specialty fern sellers)
- r/ferns (trade/sale subreddit)
- Houseplant swaps on Facebook
The bottom line
Ferns add the magic to terrariums. Start with button fern (most forgiving) or lemon button fern (compact, easy). Move to maidenhair once you have confidence.