Boston Fern Plant Care

Boston Fern (Nephrolepis exaltata) belongs to the Nephrolepidaceae family within the Nephrolepis genus. Boston Fern is native to Northern South America through Mexico, Florida and the West Indies. Boston Fern is also known as Sword fern, Fishbone fern.

Boston Fern displays a compact, upright growth habit, reaching up to 3 ft tall with a spread of approximately 4 ft. Boston Fern produces does not flower. reproduces through spores on the undersides of its leaves.

Leaf size: approximately 24 inches.

Water a young or newly planted Boston Fern every 7–10 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established shrubs mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Boston Fern thrives in bright indirect light. Avoid placing Boston Fern in direct, harsh sunlight for extended periods, as this can scorch the foliage.

Nephrolepis exaltata tolerates temperatures of 60–75°F. Boston Fern prefers humidity levels of 50–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.

Well-draining soil mix. Good drainage is essential for Boston Fern to prevent waterlogging, which leads to root rot and fungal issues.

Feed Boston Fern every month during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established shrubs in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with bright indirect light and well-draining soil mix. Avoid low spots where water collects after rain.

Boston Fern is suited to USDA Zone 9a – 11b.

Plant container-grown or balled-and-burlapped shrubs in spring or early autumn, setting the root flare at soil level, and water well after planting.

Boston Fern can spread to about 4 ft (1.2 m) and reach about 3 ft (1 m) tall. Space plants about 4 ft (1.2 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the plant spacing calculator.

Prune Boston Fern while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the shrub in one year.

Boston Fern is frost-tender (hardy to USDA zone 9). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Boston Fern can be propagated through division of root ball or spores. Similar propagation techniques also apply to lemon button fern plant care, which shares the same genus.

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Boston Fern is susceptible to spider mites, mealybugs, scale insects. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Boston Fern grows outdoors in USDA Zone 9a – 11b. It survives winters down to planting zone 9a. Boston Fern is native to Northern South America through Mexico, Florida and the West Indies. In cooler regions, grow Boston Fern as a houseplant or bring it indoors before the first frost.