Boston fern care guide

The Boston fern has long, arching fronds that spill over the sides of a hanging basket. It is a front porch classic in summer. Indoors, it needs steady water and humid air, or it sheds tiny brown leaflets all over the floor.

Light

Give it bright, indirect light, such as a spot near an east or north window. Direct sun scorches the fronds. Low light makes the plant thin and pale.

Water

Keep the soil moist, like a wrung-out sponge. Water when the top 2 cm (1 in) of soil starts to feel dry. Water until it drains, then empty the saucer.

Ferns do not forgive drying out. A fern left dry for a few days drops leaflets and gets brown, crispy patches. Soggy soil rots the roots. Read how to tell if a houseplant is overwatered or underwatered.

Hanging baskets dry out fast. Check them every few days.

Soil and potting

Use a rich, peat or coir-based potting mix that holds water but drains well.

Repot every year or two in spring, when roots fill the pot. Go up one size, or divide it. See how to repot a houseplant step by step.

Humidity and temperature

Boston ferns need humid air. Dry winter air is the top reason they struggle indoors.

A bright bathroom works well. A humidifier, a group of plants, or a pebble tray helps elsewhere. Keep it away from heat vents and fireplaces.

Keep it between 16 and 24°C (60 and 75°F). A cool room is better than a warm one.

Bringing it in for winter

Many people hang Boston ferns on the porch in summer. In a cold climate, bring it in before nights drop below 10°C (50°F).

1. Check for pests and rinse the fronds with a hose.
2. Trim off brown or damaged fronds.
3. Hang it in the brightest, coolest, most humid room you have.
4. Expect it to shed for a few weeks as it adjusts.

Some people let the fern rest in winter in a cool, bright garage or sunroom kept above 10°C (50°F), with less water. It looks rough by spring, then fills in once it goes back outside.

Feeding

Feed monthly in spring and summer with a balanced liquid fertilizer at half strength. Skip fall and winter.

Pruning

Cut brown or yellow fronds off at the soil line. Cut runners, the thin, leafless stems, if you want a neater look. Shake the plant outside now and then to drop loose leaflets.

Propagation

• Division. In spring, cut the clump into two to four pieces, each with roots and fronds. Pot each one up.
• Runners. Pin a runner onto a small pot of damp soil next to the plant. Cut it free once it roots and grows fronds.

Problems

What you see	Most likely cause
Tiny brown leaflets shed everywhere	Dry air or dry soil
Brown, crispy fronds	Soil dried out, or a heat vent
Yellow fronds, wet soil	Too much water
Pale, washed-out fronds	Too much direct sun
Thin, sparse plant	Not enough light
Gray, mushy center	Rot from soggy soil

Pests

Spider mites and mealybugs can show up in dry air. Scale looks like small brown bumps on the fronds. Fungus gnats mean the soil stays too wet. Read how to get rid of fungus gnats in houseplants.

Check any fern coming in from outside for slugs, spiders, and aphids.

Pet safety

The ASPCA lists Boston fern as non-toxic to cats and dogs. Some other plants called ferns, like the asparagus fern, are toxic. Check the botanical name.

Varieties

• ‘Fluffy Ruffles’ has short, stiff, ruffled fronds.
• Lemon button fern is small, with round leaflets. It fits on a desk.
• Kimberly queen fern grows upright and handles dry air better.
• ‘Dallas’ is a compact type that tolerates drier air.
• ‘Tiger’ has fronds striped in lime and green.