Boston fern care guide
Nephrolepis exaltata
Also known as: Sword fern, Boston fern, Nephrolepis 'Teddy Junior'
Pets and children
We haven't been able to confirm how this plant affects pets or small children. If any is eaten, consult a veterinarian or a doctor.
How often to water Boston fern
- Spring–Summer (Mar–Sep)
- Every 3 days
- Water well once the topsoil dries and do not let it dry right out, as a guide; check daily in summer, when it dries fast, and mist as well.
- Autumn (Oct–Nov)
- Every 4 days
- Drying slows, so generally water about a day after the surface dries.
- Winter (Dec–Feb)
- Every 7 days
- Water sparingly about two to three days after the soil dries, and mist to offset heated air.
Light and placement for Boston fern
Bright shade out of direct sun is about right, such as a north window or light through a sheer curtain; strong sun yellows and scorches the fronds.
Overwintering Boston fern
Overwintering guide: 5°C (41°F) or above
It takes down to about 5°C, but winter is easier in a bright spot indoors; dry heater air makes the leaflets shed, so keep it out of drafts and keep misting.
Fertilizing and repotting Boston fern
Fertilizer
Diluted liquid fertilizer about every two to three weeks from May to September; strong feeds burn the frond tips, so keep it weak, and none in winter.
When to repot
Spring–Summer (Mar–Sep)
Common problems with Boston fern
- In a dry room the leaflets brown and drop.
- Drying out browns the whole plant.
- Water left in the saucer rots the roots.
Tips for growing Boston fern
- Cut old brown fronds off at the base to make room for new ones.
- Plantlets on the runners can be cut off and potted.
- An occasional shower rinses off dust and spider mites.
These are AI-generated general guidelines. They vary with the variety, the placement and the pot size. For effects on pets or children, consult a veterinarian or a doctor.
Keep your plant log going
Greenery is a free app that keeps your plant care going, with watering reminders and photo records. Available on iOS and Android.
