Boston Fern vs. Sword Fern: Two Similar Looking Plants Often Confused For Each

Written by Sandy Porter
Updated: November 14, 2022
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If you’ve ever walked through forests in America, you’ve likely caught glimpses of one of the most prevalent plants in the western world: ferns. And likely, if you’ve ever kept any ferns at home, you’ve identified one of these familiar plants growing along the trails but may not have known the difference between Boston vs. sword fern.

If you look online, you’ll find some confusing information stating that they’re the same plant. However, if you dig in, you’ll find some subtle differences that can help you better understand why they thrive indoors (or outdoors) in your area, which plant is which, and how you should best care for them.

Boston fern as hanging plant

Boston ferns make amazing hanging plants for both indoor and outdoor use.

©aon168/Shutterstock.com

Boston FernSword Fern
ClassificationNephrolepis exaltata ‘Bostoniensis’; There are approximately 30 cultivars under the name Boston fern.Polystichum munitum; about 260 species exist across the plant
DescriptionWith broad fronds reaching 6 inches in width, Boston ferns are large, lovely, frilly looking ferns that come in pale to medium green shades.Often growing fronds as long as 5 feet in length, sword ferns are made up of a cluster of these fronds that look like sword blades and come in dark green “crown” shaped plants.
UsesBoston ferns make amazing indoor plants, especially for bathrooms, darkened rooms, and homes with cats and dogs.Sword ferns have been used indoor and outdoor plants, for arts and crafts, and for treating certain illnesses, including sore throat, nettle stings, diarrhea, and helping ease childbirth pain.
Origin and Growing PreferencesBoston ferns originated in tropical and subtropical areas of Mexico, South America, Central America, Polynesia, Africa, the West Indies, and the southeastern United States. They thrive in high humidity areas.Sword ferns originated in Africa, the West Indies and the Americas, and thrive in dark, damp places. They do well as indoor plants as long as they receive some sunlight and are kept moist.
Special Features and Fun FactsThe Boston fern is great for beginners, is recognized by NASA for pretty amazing things, and naturally loves to grow on Sabal palmetto trees.The Sword Fern is often used for making Christmas wreaths, earning it the nickname of Christmas fern. They also produce interestingly little “baby” fern plants called sporophytes.

Key Differences Between Boston Fern and Sword Fern

There are some subtle but key differences between Boston ferns and sword ferns. Check them out below to see which plant you’ve really got at home or which one you ought to.

Boston Fern vs. Sword Fern: Classification

Boston fern as hanging plant

Outward arching fronds of the Boston fern

©Jeerayut Rianwed/Shutterstock.com

An ornamental plant in most understandings, Nephrolepis exaltata, or Boston fern, is part of the same family as the sword fern. Boston ferns, however, look different and behave differently, and grow differently. They are both part of the Lomariopsidaceae family. The Boston fern’s specific name is Nephrolepis exaltata ‘Bostoniensis’ and was discovered in a large shipment of various ferns headed from the West Indies or Florida into the Boston area, earning its name for it.

Polystichum munitum, or sword fern, is part of the same family as the Boston fern, and is considered an evergreen perennial fern. This is one of the most abundant wild ferns in the forested areas of the Americas.

Boston Fern vs. Sword Fern: Description

Boston ferns have broad fronds with alternating pinnae on either side of the central line of the leaves. The leaves tends to grow medium to pale green and get as wide as 6 inches. The fronds have two rows of round clusters of spore-bearing organs known as sori near the margins on the underside of the leaves. Ferns themselves are seedless, so they bear plants through these spores. The leaves usually have undulating edges or look serrated. The fronds of Boston ferns arch downward.

Sword ferns are even larger plants, often growing 5 feet and taller. They have long blades that sort of look like swords (thus the name) and create a large “crown” shaped plant. Each blade or frond has alternating leaflets along the stem or center stipe. They are basically a large, perennial clump of leaves that spread out from the center. At the center, there is a woody mass, which is the root-stems (or rhizomes) with reddish brown scales on the outside. The fronds are dark green and often grow as long as 5 feet in length. The fronds of sword ferns are upright.

Boston Fern vs. Sword Fern: Uses

Potted Boston fern placed on table in cozy sitting corner

Boston ferns make amazing indoor plants, no matter the space.

©Studio Light and Shade/Shutterstock.com

One of the ways that both of these ferns is used is as bathroom plants. The two ferns thrive in moist, high humidity environments and help to suck out the water and even some toxins from the air.

Boston ferns make amazing indoors plants almost anywhere in the house, though, save in extremely sunny windows. They also work well as outdoor plants, though if you live where it’s cold, it’s best to keep them potted so you can bring them indoors in cooler months. They make for amazing hanging plants, container plants, and raised garden bed plants.

Potted sword fern on greay concrete background

Identify sword ferns by their upright fronds.

©dopdop/Shutterstock.com

Sword ferns are great for indoor plants as well, in darker, damper places, though they do need some light. They are great as hanging plants, potted plants, raised bed plants, and even standard outdoor plants, as long as you live in subtropical to tropical regions. Be sure not to plant them in too sunny a location, though, as they won’t do particularly well there.

Sword fern fronds have been used for arts and crafts projects for many years, as well, in homemade candles, or ink them and use them as stamps. They have also been used to cure diarrhea and nettle stings. They’ve also been used by the Swinomish tribe to treat sore throats and to help ease childbirth pain.

Boston Fern vs. Sword Fern: Origins and Growing Preferences

Originating in humid tropical and subtropical locations like Mexico, South America, Central America, Florida, Polynesia, parts of Africa, and the West Indies, the Boston fern remains a fascinating plant that thrives in humid climates. This helps make them perfect for bathrooms and other high humidity spaces, as they’re truly thrive here.

These gloriously leafy plants do best in well-drained but moisture-retaining soil or in soilless potting medium like vermiculite mixed with peat. They need the soil kept medium moist and do best when they’ve been spritzed with some water regularly or kept in high humidity areas like bathrooms and kitchens. It’s recommended you double pot them to keep moisture in the bowl beneath the pot in which they are potted.

Sword fern in red pot

Sword ferns do well as indoor plants or potted plants for the patio.

©Totokzww/Shutterstock.com

Sword ferns originated in Africa, the West Indies, and the Americas, as well, thriving in swamplands, shaded forests, and bayous. These ancient plants love high humidity regions, much like Boston ferns, but they’ve been kept as indoors plants since at least the Victorian era when displaying exotic plants was in vogue.

Sword ferns do well in dark, damp areas of the house, like bathrooms, kitchens, and other high humidity areas. But they do need some, regular light, so skip the basement or attic! Keep them mostly shaded, though, in medium moisture soil. Regularly spritz them with some fresh water and double pot them for best results.

Boston Fern vs. Sword Fern: Special Features and Fun Facts

The Boston fern is perfect for beginners – the simple plant doesn’t need much care and is about as tough as any indoor-friendly plant can get. This fern is so amazing that NASA actually recognizes it for its cleaning qualities. It can literally remove cigarette smoke and formaldehyde from the area. The Florida Ruffle is the most popular of the 50+ cultivars of the Boston fern and it naturally grows on Sabal palmetto trees. So, if you’re ever walking around in Florida and notice some fern-like leaves growing out of the trunk of a palmetto tree, well, guess what – you’re right! Plus, Boston ferns are non-toxic for cats and dogs.

The Sword Fern is also known as the Christmas fern thanks to its frequent use in the making of holiday wreaths. Interestingly enough, this fern also exists in a less recognizable form. It produces by spores contained in half the chromosomes needed for a mature plant, so when the reproduction of the fern happens, these little sporophytes leave the plant front and go to the ground where they can then grow. You might see them and think they’re odd looking little plants but, in fact, they’re actually just really young sword ferns.

Misting potted ferns on a windowsill

Ferns thrive as indoor plants but especially when they’re regularly misted.

©New Africa/Shutterstock.com

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The photo featured at the top of this post is © aon168/Shutterstock.com


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About the Author

Sandy Porter is a writer at A-Z Animals primarily covering house garden plants, mammals, reptiles, and birds. Sandy has been writing professionally since 2017, has a Bachelor’s degree and is currently seeking her Masters. She has had lifelong experience with home gardens, cats, dogs, horses, lizards, frogs, and turtles and has written about these plants and animals professionally since 2017. She spent many years volunteering with horses and looks forward to extending that volunteer work into equine therapy in the near future. Sandy lives in Chicago, where she enjoys spotting wildlife such as foxes, rabbits, owls, hawks, and skunks on her patio and micro-garden.

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Sources
  1. Wisconsin Horticulture Division of Extension, Available here: https://hort.extension.wisc.edu/articles/boston-fern-nephrolepis-exaltata-bostoniensis/
  2. Missouri Botanical Garden, Available here: https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c548
  3. Wikipedia, Available here: https://en.wikipedia.org/wiki/Nephrolepis_exaltata
  4. Ferns n Petals, Available here: https://www.fnp.com/article/interesting-things-to-know-about-boston-fern-plant
  5. Royal BC Museum, Available here: https://staff.royalbcmuseum.bc.ca/2016/11/28/sword-fern/
  6. SF Gate, Available here: https://homeguides.sfgate.com/interesting-western-sword-fern-70704.html
  7. Get Planta, Available here: https://getplanta.com/article/trivia/swordfern
  8. Wikipedia, Available here: https://en.wikipedia.org/wiki/Polystichum_munitum