Nephrolepis exaltata

Sword Fern, Boston Fern, Wild Boston Fern, Bostonfern

Easy careTerrestrialNon-toxic30–90 cm

A vigorous fern native to tropical and subtropical Americas, from Florida and the Caribbean south to Brazil. Long, arching fronds radiate from a central crown, and the plant spreads through stolons — wiry runners that root wherever they touch moist substrate. It does best in high humidity and consistently moist soil, conditions that reflect its swamp-forest origins. A large closed terrarium or paludarium suits it well. Non-toxic to cats, dogs, and horses.

Build a terrarium with this plant
Sword Fern image

Care

Prefers high humidity, indirect light, with 16–24 °C, and reaches 90 cm at maturity.

Light

Indirect light(preferred)Shade tolerantBright indirect

Humidity

High (60–80%)(preferred)Very high (80%+)Medium (40–60%)

Temperature

10°C25°C40°C
16°C – 24°C

Soil

Loamy(preferred)Moisture retentivePeat moss

Moisture

Moist(preferred)

Soil pH

5.5 – 6.5

Propagation

Divide crowded clumps in spring, separating sections that each have fronds and roots. Pot each division in moist, loamy mix and keep humidity high until established.

Native range

Native to Northern South America, North-Central Pacific, Southwestern U.S.A., South-Central U.S.A., Southeastern U.S.A., Mexico, Central America, Caribbean, Western South America, and Brazil.

Appearance

Growth habit

UprightClumping

Leaf shape

Compound

Leaf texture

FeatherySmooth

Frequently asked

Can Sword Fern grow in a closed terrarium?

Yes. Sword Fern prefers high (60–80%) humidity, which is what a closed terrarium provides, and tolerates indirect-light-loving conditions.

Does Sword Fern need drainage?

Sword Fern prefers a moist substrate. Drainage is helpful but not critical; consistent moisture matters more.

What humidity does Sword Fern need?

Sword Fern does best in high (60–80%) humidity.

Is Sword Fern pet-safe?

Sword Fern is considered non-toxic to common household pets.

How tall does Sword Fern grow?

Sword Fern typically reaches 30–90 cm at maturity.

How do you propagate Sword Fern?

Sword Fern can be propagated by division or runners or spores.

References

  1. 1

    Kew Plants of the World Online — Nephrolepis exaltata (L.) Schott

    https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:17160830-1
  2. 2

    NC Extension Gardener Plant Toolbox — Nephrolepis exaltata

    https://plants.ces.ncsu.edu/plants/nephrolepis-exaltata/
  3. 3

    Terrarium Tribe — Nephrolepis exaltata (Sword Fern)

    https://terrariumtribe.com/terrarium-plants/nephrolepis-exaltata-sword-fern/
  4. 4

    Missouri Botanical Garden Plant Finder — Nephrolepis exaltata

    https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c548
  5. 5