Boston fern care: watering, light and repotting
Also called nephrolepis, fern, sword fern · Nephrolepis exaltata · Nephrolepidaceae family
5 d in winter
How often to water the Boston fern?
Allow about 3 days between waterings in spring and summer, and 5 days in autumn and winter, when growth slows down. These rhythms apply to a room with its favourite light: in a darker room the plant drinks less; in a brighter one, it drinks more.
Must never dry out completely. Perfect in a bright bathroom.
Misting every 2 days helps keep the air humid around its leaves, especially in winter when central heating dries the house out.
What light does it need?
The Boston fern likes bright but filtered light: near an east- or west-facing window, or a little back from a south-facing one. Direct afternoon sun can mark the leaves.
Repotting and fertiliser
Repot every 2 years, ideally in April, into a pot only slightly bigger than the last one. As for fertiliser, from April to September, feeding every 30 days is enough; the rest of the year, let it rest.
Adult size: 16–36 in (40–90 cm).
Safe for cats and dogs, according to the ASPCA.
Common problems
Leaflets drying and dropping
Cause: Dry air or dry soil. What to do: Mist daily in winter and keep the soil moist.
Yellow fronds
Cause: Too much sun. What to do: Give it indirect light.
Frequently asked questions
How often should you water the Boston fern?
About every 3 days in spring and summer, and every 5 days in autumn and winter, in a room with its favourite light. The darker the room, the longer you wait between waterings. Before watering, check that the top inch of soil has dried.
Where should you put the Boston fern?
The Boston fern likes bright but filtered light: near an east- or west-facing window, or a little back from a south-facing one. Direct afternoon sun can mark the leaves.
Should you mist the Boston fern?
Yes, misting every 2 days does it good, especially in winter when heating dries the air. Use soft, room-temperature water.
When should you repot the Boston fern?
Every 2 years, ideally in April, or sooner if roots come out of the drainage hole. Choose a pot only slightly bigger, 1 to 1.5 in (2 to 4 cm) wider, always with a hole in the bottom.
Cats, dogs, children: is the Boston fern safe?
The Boston fern is listed as non-toxic to cats and dogs by the ASPCA. A pet that eats a lot of it may still vomit, so it's best not to let it nibble.
Is it an easy plant to care for?
Fairly: the Boston fern needs a little attention, mostly with watering and light. Nothing complicated with a reminder at the right time.
These are guidelines for an indoor plant in a temperate climate. Trust the soil too: a finger pushed an inch into it will tell you whether it's thirsty.