If your fern is shedding leaflets on the carpet or turning crisp at the edges, the cause is nearly always moisture. Either the compost dried out or the air did, and in a centrally heated winter it's often both. Iowa State University Extension notes that many houseplants like 40–50% relative humidity, and that homes in winter can drop to 10–20%. Ferns feel that first. The fix isn't a spray bottle. It's steady compost and a better spot.
01At a glance
- Never let the compost dry out: keep it evenly moist, never soggy. This matters most with maidenhair.
- Pick the room, not the gadget: a bright bathroom or kitchen does more than misting.
- Bird's nest fern: water the compost round the edge of the pot. Keep water out of the central crown.
- Crisped fronds: cut them off at the base. New ones grow if you fix the cause.
- Misting: a brief lift, not a fix.
02The three ferns, compared
Boston fern. The one people buy most. The University of Wisconsin Extension says to keep the compost evenly moist but not saturated, in medium bright light such as an east window. It warns that dry winter air browns the tips and edges of the leaflets. If yours is dropping leaflets, check the compost first, then the air, then whether it's next to a radiator or a cold draught.
Maidenhair fern. The fussiest. Clemson Extension puts it bluntly: "Maidenhairs are difficult to grow in most homes." It needs humidity of about 50% and compost that is moist at all times. The RHS suggests standing the pot on a tray of moist gravel and watering sparingly in winter. Sparingly means less, not dry. One full dry-out can brown the whole plant.
Bird's nest fern. The easiest of the three. Clemson Extension calls it easy to grow and gives ideal temperatures of 13–21°C. Its weak point is the fuzzy crown in the middle of the rosette. Clemson's own guide says to water around the outer edge of the pot so water doesn't get into the centre, and to keep water off the leaves.
03Getting the watering right
- Check the surface every few days in winter. Heated rooms dry pots faster than you'd expect.
- Water when the surface just starts to dry. For a bird's nest fern, Clemson suggests when the top inch (about 2.5cm) feels dry. Don't wait for the whole pot.
- Use room-temperature water. The University of Minnesota Extension warns that cold water can damage tropical roots, and that softened water builds up salts.
- Pour onto the compost, not over the fronds, and for a bird's nest fern, round the rim only.
- Let it drain, then empty the saucer. A pot standing in water rots the roots.
04Humidity: what actually helps
Be honest with yourself about misting. The University of Minnesota Extension says it "is not very effective" and can encourage leaf-spot disease. Nebraska Extension adds that even misting several times a day has little benefit. Clemson allows an occasional light mist, so it does no harm, but it won't save a crisping fern.
Things that do more, roughly in order of cost:
- Move it. A bright bathroom or kitchen is naturally more humid. Nebraska Extension calls this the low-cost option.
- Group plants together. Iowa State says clusters of plants raise the humidity around them.
- A pebble tray. Fill a tray with gravel and water to just below the top of the stones, so the pot sits above the waterline. It creates a small humid zone round the plant. Don't expect a big change to the room.
- Double-potting. Stand the pot inside a larger one and pack the gap with damp moss. Both Clemson and Wisconsin suggest it.
- A humidifier. Iowa State rates them highly. They're the most expensive option, so keep one for a maidenhair you really care about.
05Is it dry air, drought or too much water?
- Crisp brown tips and edges, leaflets dropping: dry air or compost that dried out. Raise the humidity and water more steadily.
- Whole fronds crisped overnight (maidenhair): almost always a dry-out. Cut them off at the base and keep the compost damp. It often regrows.
- Brown, mushy, sour-smelling centre (bird's nest): water sat in the crown. Change how you water, and act fast.
- Yellow, limp fronds and wet compost: too much water, or too cold. Let it drain properly.
- Pale, scorched fronds: too much direct sun. Move it back from the window.
Also look under the fronds. Clemson lists scale and mites as the main pests, and Wisconsin adds mealybugs.
Before placing a maidenhair or bird's nest fern where children or pets can reach it, check the safety flags on our maidenhair fern and bird's nest fern profiles.
How we checked this
Every care and safety claim on this page is verified against horticultural and veterinary sources.
Sources: RHS — Adiantum raddianum · Clemson Cooperative Extension — Indoor ferns · Clemson Cooperative Extension — How to grow and care for bird's nest fern · University of Wisconsin Extension — Boston fern · University of Minnesota Extension — Tropical ferns · Nebraska Extension — Dry air is murder on ferns · Iowa State University Extension — How can I raise the relative humidity indoors for my houseplants?
Checked 8 October 2026. If our advice ever conflicts with the RHS, believe them and tell us.