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Nephrolepis exaltata

Nephrolepis exaltata (Boston Fern) Care Guide

Updated by Funfactorium Editorial1 min readFor fun · sources cited
Photo: Unknown · CC BY-SA 3.0
In short

Nephrolepis exaltata is the Boston fern, a tropical American sword fern that became the classic Victorian parlour plant and remains one of the most-grown indoor ferns. Its arching, finely divided fronds make a soft contrast to glossier foliage plants. It needs higher humidity than most houseplants and is happiest in bathrooms or near a humidifier.

Care facts at a glance

Light
Bright indirect
Water
Keep the mix consistently lightly moist; water as soon as the top dries.
Humidity
50–70 %
Temperature
15–24 °C
Soil
Peat-rich, well-draining mix with perlite; slightly acidic.
Origin
Tropical Americas, Africa, and Polynesia.
Mature size
60 to 90 cm tall, similar spread.

Overview

Nephrolepis exaltata became the iconic Victorian parlour plant in the 1880s when a sport called the Bostoniensis cultivar was discovered in a shipment to Boston. Modern Boston ferns are typically Bostoniensis or one of its descendants.

Care Priorities

  • Higher humidity than most houseplants — bathrooms and grouped plants help.
  • Bright filtered light; deep shade thins the fronds.
  • Keep mix consistently moist; never let it dry out.
  • Trim brown fronds at the base; new ones emerge from the rhizome.

Common Problems

Brown crispy fronds are dry air or hard water. Yellow fronds are overwatering. Massive frond drop after a winter heating spell is a humidity crisis — move to a more humid spot.

Sources & further reading (2)
  1. encyclopedia — accessed 2026-04-28
  2. botanical-garden — accessed 2026-04-28

Frequently asked questions

Why does my Boston fern keep dropping leaves?

Almost always low humidity or inconsistent watering. Move to a humid bathroom and water on a steady rhythm.

Can I keep it in a regular living room?

Yes, but expect more frond loss than in a humid space. A pebble tray or small humidifier helps a lot.

How often to repot?

Every 18 to 24 months, or when the rhizome fills the pot. Boston ferns dislike being root-bound.

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