Sword Fern/ Boston Fern

Nephrolepis exaltata 'Fluffy Ruffles'

Nephrolepis exaltata is a lusciously thick evergreen fern with beautiful sword-shaped leaves. In its larger native form (the Boston Fern) it’s a super popular houseplant, and has been since the Victorian period. Thankfully for us, it also comes in a few dwarf varieties that are perfect for terrariums – this ‘Fluffy Ruffles’ cultivar and the ‘Marisa’ being two of them. This miniature fern only grows up to 12 inches and has a characteristic fluffy texture.

At a Glance

Where to Buy Nephrolepis exaltata (Miniature Varieties)

See the links below to purchase from reputable terrarium plant shops and marketplaces (may include affiliate links). 

Terrarium Plant Guide

Nephrolepis exaltata Care & Growth

Lighting

In a terrarium, Nephrolepis exaltata will do best with plenty of bright, indirect light. They can handle some direct winter sun but are still prone to scorching.

Watering

Like most ferns, Sword Ferns grows best with constant, even moisture. They can be quite sensitive and have very little drought tolerance.

Substrate

Originating from humid swamp environments (unsurprisingly not Boston, despite the common name) Nephrolepis exaltata prefers a substrate that’s rich in moisture and organic materials. A tropical terrarium substrate with good water retention and drainage will work best.

Temperature & Humidity

Sword Ferns love a humid environment and will need well over 50% to grow properly. They are tropical plants, and will do well in the higher temperatures usually found in a tropical terrarium, but they actually do great when they’re a bit cooler too.

Growth

Under the right conditions, Nephrolepis exaltata can grow fairly quickly and widely, and so may need regular pruning.

Propagation

Sword ferns belong to a type of plants which reproduce via spores, though it’s not true of all varieties. The ‘Fluffy Ruffles’ cultivar is sterile and doesn’t contain spores. Thankfully, there’s another way to propagate Sword Ferns, and that’s through division. Simply divide a healthy plant, ensuring each division has its own section of healthy roots and plant as you normally would.

Varieties & Similar Plants

The classic Boston Fern comes in a wide range of cultivars, most of which are large and more suited as houseplants. The ‘Marisa’ and ‘Fluffy Ruffles’ are the smallest varieties, though the `Bostoniensis Compacta’ cultivar may fit larger terrariums.

Common Problems

As Nephrolepis exaltata is sensitive to moisture and humidity, most of the visible issues are due to these. Yellowing leaves are a sign of too little humidity, and shedding fronds are a sign of excessive dryness.