Boston fern care and growing guide: expert tips to master

Our advice for Boston fern care will keep your plants looking lush and leafy all year round

Pot of hanging Boston fern, hanging green plant decoration
(Image credit: JADEZMITH / Getty)

Also known as the sword fern, the Boston fern is an elegant houseplant, that will create a lush look in your home, with its fountain of bright green frilly foliage. 

The arching leaves, known as fronds, can grow up to 3ft (90cm) in length, given the right conditions, and make a beautiful feature when cascading from a hanging basket or displayed in a pot on a tall stand. 

Boston ferns (Nephrolepis exaltata) hail from the forests of South and Central America, and consequently prefer a warm humid atmosphere that replicates their native habitat. However, while this fern comes from swampy areas, it is an epiphyte, which means it lives among the branches of trees, so it will not be happy in sitting in soggy soil.

You may find the Boston fern listed under Nephrolepis exaltata ‘Bostoniensis’ which is a popular plain green variety. Or try the variegated form N. exaltata ‘Tiger Fern’, with its unusual yellow-streaked foliage, which is also one of the best indoor plants

Bush of nephrolepis window background

In a south-facing room, place your fern away from the window where the bright glare of the sun may scorch the foliage

(Image credit: Victor Aksyonov / Alamy Stock Photo)

3 essential Boston fern care tips to follow

Tom Knight of Our House Plants says the Boston fern is a good choice for beginners wanting to start their own indoor garden: 'It’s readily available, relatively cheap and offers a great way to enjoy lush green foliage, in the feelings of tranquility it seems to evoke.'

1. Find the right light for your Boston fern

Tom Knight says this fern likes a bright or slightly shaded position: 'The Boston fern is really versatile. You can grow it on a north- or east-facing windowsill or in a sunnier room, setting it back a little.' 

'Just make sure you avoid spots in very low light, or in harsh sunshine such as on a south-facing sill.' He also suggests growing them as a bathroom plant, if the light conditions are right, or as a steamy kitchen plant, where humidity levels are high. 

Circular mirror with diagonal paintwork in bathroom with rope shelf

A steamy bathroom with its high humidity levels will help to keep a Boston fern healthy

(Image credit: Andreas von Einsiedel / Alamy Stock Photo)

2. Water and feed as required

Make sure your fern’s compost is consistently moist from spring to fall. But, as with many houseplants such as the yucca or Chinese money plant, guard against soggy, wet soil by planting it in a pot with drainage holes in the base. 

Tom adds: 'Mine sits on an east-facing windowsill and I need to water it once a week, sometimes more in very warm weather.' Reduce watering in winter, applying moisture only when the top of the compost feels dry. 

If you are displaying your Boston ferns in a living or dining room, or as bedroom plant, where humidity levels are low, also be prepared to mist the leaves a couple of times a week. Or stand the plant in its pot on a tray filled with pebbles and topped up with water. 

Feed with a half-strength liquid fertilizer once a month from spring to early fall to keep the foliage green and lush.

Nephrolepis plants, fern. Stylish green plant in ceramic pots on wooden vintage stand on background of gray wall.

Display your fern on a tall stand or shelf to enjoy its cascading fountains of green foliage

(Image credit: Konstantin Malkov / Alamy Stock Photo)

3. Keep the atmosphere moist

Like orchids, Boston ferns like humidity. The fronds may turn brown if the compost or atmosphere is too dry. Water well, making sure that you don’t overwater. As with pothos care, soggy compost can result in wilting or yellowing leaves and may cause the roots and fronds to rot. 

Ideally, water over a sink and leave to drain before replacing your fern in its waterproof container. If the atmosphere is dry, mist the leaves regularly.

If you find dark brown spots beneath the fronds of a Boston fern, do not panic. These are not a pest or disease but the ‘spores’ by which ferns reproduce, although as per calathea propagation, it is much easier to propagate this fern by division (see below).

Blond woman spraying fern, fertilizing plants indoors

Where humidity levels are low, such as in a living room, mist the fern’s leaves a couple of times a week

(Image credit: Olga Rolenko / Getty)

Common problems with Boston ferns

Boston ferns suffers from very few diseases and pests, although like philodendrons you might find that mealybugs and scale insects may occasionally attack it. Mealybugs looks like little woodlice and hide beneath a white fluffy coating, while scale look like hard little shells. 

Both suck the sap from plant stems, leading to distorted growth. Try washing off these insects and the scale’s white, waxy eggs with a damp cloth. If this does not work, soap-based insecticides may remove both scale and mealybugs.

Or, for persistent infestations, try dabbing them with a cotton wool bud soaked in a little methylated spirit (test a small area first to ensure it does not harm your plant). This method will work on other infected houseplants including kentia palms and Maidenhair ferns.

Beautiful fern leaves. Nephrolepis exaltata Tiger Fern, Boston Fern.

‘Tiger Fern’ is an unusual variegated form of Boston fern, with pale yellow and green patterned fronds

(Image credit: Techa Tungateja / Alamy Stock Photo)

Can I put my Boston fern outside?

Christopher Young, leader of the glasshouse team at RHS Garden Wisley in the UK, says that your Boston fern will be happy outside during the summer months. 

He adds: 'Just make sure you place it in partial shade, out of the midday sun. It would also be best to gradually introduce the fern to outside living, by placing it in the backyard during the day, but bringing it back inside at night for a week or two, before putting it out permanently. It should then be okay in temperatures down to about 50˚F (10˚C).'

Boston Fern (Nephrolepis exaltata) in a pot on a terrace

You can place your Boston fern outside during the summer months when temperatures reach about 50˚F (10˚C) at night

(Image credit: BIOSPHOTO / Alamy Stock Photo)

How do I propagate a Boston fern?

Unlike rubber plant propagation which is done via cuttings, Christopher says that the best way to propagate this fern is through division. 'Divide your plant in the spring, so it can re-establish over the summer months.' 

To do this, water the plant well and remove the rootball from its pot. Then, either use your hands to prize apart rooted sections with the leaves attached, or take a sharp, clean knife and cut the rootball into a few pieces. 

Pot up each new rooted section in a 50:50 mix of fresh multipurpose compost and soil-based compost, in containers just large enough to accommodate the roots. Discard any sections with brown, dried leaves or unhealthy dark-colored roots.

Leaves of fern on a white background

Bright green fronds with a lacy appearance will lend a cool leafy look to your home

(Image credit: Tatyana Abramovich / Getty)

How long does a Boston fern live?

Christopher says: 'I don’t know exactly how long this species lives for, but ferns tend to be long lived, so with careful cultivation they should survive for many years.'

Where to buy Boston ferns

Shop Boston ferns in the US:

Shop Boston ferns in the UK:

Zia Allaway
Freelance writer

Zia Allaway is a garden book author, editor, and journalist, and writes for a range of gardening and women’s magazines, including Easy Gardens, Homes & Gardens and Livingetc, as well as The Guardian and The Daily Telegraph newspapers. She has also written books for the Royal Horticultural Society and Dorling Kindersley publishers, including Eco-Gardening, Compost, Low Maintenance, Practical House Plant Book, Practical Cactus & Succulent Book, Indoor Edible Garden, What Plant Where, and the Encyclopedia of Plants and Flowers.