Boston Fern Care: Light, Water, Humidity and Leaf Drop Fixes

A healthy Boston fern is one of the most beautiful houseplants you can grow: a fountain of soft, arching fronds that looks stunning in a hanging basket. It also has a reputation for dropping leaflets all over the floor. The reason is almost always the same: indoor air that’s too dry and soil that’s been allowed to dry out. Fix those two things and a Boston fern becomes much easier to keep.

Boston fern care at a glance

Need	What a Boston fern wants
Light	Bright, indirect or filtered light; no direct afternoon sun
Water	Keep evenly moist; water when the surface just starts to dry
Humidity	50% or higher
Temperature	60 to 75°F (16 to 24°C) by day; slightly cooler at night is fine
Soil	Rich, moisture-holding potting mix with a drainage hole
Fertilizer	Half-strength liquid feed monthly from spring to late summer
Size	Fronds typically 1 to 3 feet long
Pets	Non-toxic to cats and dogs (ASPCA)

How much light does a Boston fern need?

Boston ferns like bright, indirect or filtered light, like the dappled light under trees. A spot near an east or north window, or a few feet back from a bright south or west window, is ideal. Direct afternoon sun scorches the fronds, turning them pale and crispy, while a dark corner leads to thin, sparse growth and yellowing. See our lighting guide.

How to water a Boston fern

Boston ferns need evenly moist soil at all times. Water as soon as the surface starts to feel dry, which can be every 2 to 3 days in a warm, bright room and about once a week in cooler weather. Letting the soil dry out completely is the fastest way to get crispy fronds and falling leaflets.

1. Touch the soil surface every couple of days.
2. As soon as it feels just dry, water thoroughly until it drains from the bottom.
3. Empty the saucer so the roots don’t sit in water.
4. For a dense, dried-out root ball, soak the whole pot in a bowl of water for 15 to 20 minutes, then drain.

More in our watering guide.

Humidity: what keeps fronds green

Boston ferns need high humidity, ideally 50% or more. Most heated homes in winter are much drier, which is why ferns often struggle from autumn to spring.

• Use a humidifier nearby. This makes the biggest difference.
• Grow it in a bright bathroom or kitchen, where the air is naturally more humid.
• Group it with other plants.
• Double-pot it: set the pot inside a larger container packed with damp sphagnum moss.
• Keep it away from radiators, fireplaces, heating vents and air-conditioning.

Light misting helps a little but doesn’t last long, so pair it with one of the methods above. See our humidity guide.

Temperature

Boston ferns prefer moderate temperatures of 60 to 75°F (16 to 24°C), with slightly cooler nights. They struggle in hot, dry rooms and are damaged by frost, so keep them away from heaters and cold drafts.

Best soil and pot

Use a rich, moisture-holding potting mix, such as houseplant mix with some peat-free coir or compost added, that still drains freely. A plastic or glazed pot or a lined hanging basket keeps soil moist longer than terracotta. Always use a drainage hole; soggy soil leads to root rot. See our potting soil guide.

Fertilizing a Boston fern

Ferns are light feeders. Use a liquid houseplant fertilizer at half strength about once a month from spring to late summer, on damp soil. Don’t feed in winter, and don’t feed newly repotted ferns for a few months. Too much fertilizer burns the delicate roots and browns frond tips. See our fertilizing guide.

Bringing a Boston fern indoors for winter

Many people grow Boston ferns outside on a porch in summer. To keep yours through winter:

1. Bring it in before night temperatures drop below 50°F (10°C).
2. Check carefully for pests and hose off the fronds before bringing it inside.
3. Trim off any brown or tired fronds at the base.
4. Give it your brightest spot out of direct sun, away from heating vents.
5. Keep the soil moist and humidity as high as you can. Some leaflet drop as it adjusts is normal.

How to propagate a Boston fern

Boston ferns don’t grow from cuttings, but they’re easy to multiply. The simplest way is division in spring, ideally when repotting a crowded plant.

1. Water the fern the day before.
2. Slide it out of its pot and find natural clumps, each with fronds and roots.
3. Cut through the root ball with a clean, sharp knife to separate the clumps.
4. Pot each section in fresh, damp mix at the same depth as before.
5. Keep the new plants moist, humid and in bright, indirect light while they settle.

Boston ferns also send out runners: thin, fuzzy stems without leaves. Pin one onto a small pot of damp mix next to the plant; once it roots and grows new fronds, cut it free. See our propagation guide.

Common Boston fern problems and fixes

What you see	Most likely cause	What to do
Leaflets dropping everywhere	Dry air or dry soil	Raise humidity; keep the soil evenly moist
Brown, crispy fronds	Low humidity, drying out or hot sun	Humidifier, steady watering, bright indirect light
Yellow fronds, soil wet	Overwatering or poor drainage	Let the surface dry slightly; check the drainage hole
Yellow fronds, soil dry	Underwatering	Soak the root ball; water more often
Pale, washed-out fronds	Too much direct sun	Move to filtered or indirect light
Thin, sparse growth	Too little light or crowded roots	More light; divide or repot in spring
Webbing or tiny moving dots	Spider mites	Rinse the fronds; raise humidity; test any spray on one frond first

Cut fully brown fronds off at the base to make room for new growth. Ferns are sensitive to some sprays, so test any treatment on a small area first. More help in our guide to houseplant pests.

Easier ferns if yours keeps struggling

If your home is dry and your Boston fern keeps shedding, these relatives are more forgiving:

• Kimberly Queen fern (Nephrolepis obliterata): upright fronds and better tolerance of drier air.
• Bird’s nest fern (Asplenium nidus): solid, wavy fronds that don’t shed leaflets.
• Rabbit’s foot fern (Davallia): fuzzy creeping rhizomes and good tolerance of normal home conditions.
• Lemon button fern (Nephrolepis cordifolia ‘Duffii’): compact and tidy.

See all our beginner-friendly picks in houseplant varieties.

Is Boston fern safe for pets?

Yes. The ASPCA lists Boston fern as non-toxic to cats and dogs, so it’s a great choice for pet owners, although cats sometimes enjoy batting at the fronds. Note that asparagus fern is not a true fern and is toxic. See our list of pet-friendly houseplants.

Quick action checklist

Save this for later: pin the cheat sheet below to your Pinterest plant board.

Boston fern care FAQ

Sources and further reading

Want to go deeper? These university extension and expert resources cover the same topic:

• Clemson Cooperative Extension: Indoor ferns
• UF/IFAS Extension: Boston fern (Nephrolepis exaltata)
• University of Wisconsin Extension: Boston fern
• ASPCA: Boston fern toxicity