Nephrolepis exaltata 'Boston'

The nineteenth-century origin of the Boston fern

Nephrolepis exaltata is native across tropical and subtropical America and grows on trees, rocks or soil in humid habitats.

The familiar Boston fern appeared in cultivation in the United States during the 1890s. ‘Boston’ is the common trade name for the cultivar ‘Bostoniensis’.

Even moisture around an open fern crown

Give Boston fern bright filtered light and protect the leaflets from hot direct sun. Temperatures around 16–24 °C, moderate-to-high humidity and gentle airflow suit active growth.

Keep the rootball evenly moist, allowing only slight surface drying. Use an airy, moisture-retentive fern mix and keep the crown above the substrate.

Feed at low strength, remove fully brown fronds at the crown and repot when the rootball becomes crowded or the medium loses structure. Divide crowded plants or root runners while new growth is active.

Brown tips and sudden leaflet loss

• Brown tips: Check for drought, dry air, mineral buildup, heat or damaged roots. Review both pot moisture and water quality.
• Rapid leaflet loss: Stabilise the plant after severe drying, hot draughts, cold shock or relocation.
• A few old yellow outer fronds: This is normal when healthy new growth continues from the centre.
• Yellowing while the mix remains wet: Improve drainage and inspect the roots for rot.
• Yellowing in dry mix: Water thoroughly and check whether the root mass has become crowded.
• Pale weak fronds: Increase filtered light and provide light feeding during active growth.
• Bleached tan areas: Move the fern away from direct sun.
• Stippling, sticky deposits or cottony insects: Check for mites, scale or mealybugs. Remove dead wet foliage and improve airflow when spots or grey mould appear.

Nephrolepis exaltata ‘Boston’ is non-toxic to cats and dogs

• This plant is non-toxic to cats and dogs.
• Its effects on people are unclear, so keep it away from young children who may chew it.
• Eating a large amount can still cause an upset stomach. Seek medical or veterinary advice if symptoms continue.

Nephrolepis exaltata: where the name comes from

Greek nephros, kidney, and lepis, scale, form Nephrolepis and refer to the small kidney-shaped coverings over the spore-bearing patches. Exaltata means elevated or very tall.

Heinrich Wilhelm Schott established the genus Nephrolepis in 1834 in Genera Filicum (Vienna), plate 3.

Carl Linnaeus first described it as Polypodium exaltatum in 1759 in Systema Naturae, tenth edition, volume 2, page 1326. Heinrich Wilhelm Schott later placed it in Nephrolepis as Nephrolepis exaltata in 1834 in Genera Filicum (Vienna), plate 3.