Temperature
60–75°F
Keep away from winter window glass and heating vents.
Boston fern
Nephrolepis exaltata
Boston fern wants medium light and water every 3 to 6 days, once the surface is just dry to the touch. Non-toxic to cats and dogs.
Light
Medium
LowMediumBright indirectDirect
A north window, or four feet back from an east one. An hour of direct afternoon sun is enough to scorch the fronds.
Water
Every 3–6 days
Baseline for a 6-inch pot indoors. Check first: water when the surface is just dry to the touch, not on a schedule.
Humidity
50% and up
Wants 80%. Struggles in dry winter air.
Difficulty
Demanding
Scores 4 of 5: Scores 4 of 5: nothing about its light or soil is demanding, but it drops fronds within days in dry indoor air and never fully recovers from drying out once.
Habit
Spreading
Grows to 18–36 inches. No support needed.
Non-toxic to cats and dogs
Eating a large amount of any plant can still cause mild stomach upset.
Detail for cats → Detail for dogs →
What each authority says
- ASPCA — entry for a cultivar of this species: Nephrolepis exalta bostoniensis
- Non-toxic to cats and dogs
- NC State Extension
- Entry exists and records no poison data.
Light
Medium light. A north window, or four feet back from an east one. An hour of direct afternoon sun is enough to scorch the fronds.
Water
Every 3 to 6 days in a 6-inch pot, when the surface is just dry to the touch.
Treat the interval as a starting point and the test as the actual instruction. Pot size, light level and season all move the number.
| Method | keep evenly moist |
|---|---|
| Test before watering | the surface is just dry to the touch |
Soil and potting
Three parts peat-free potting soil, one part perlite.
Repot roughly every 1.5 years, or when roots come through the drainage holes and water runs straight through without absorbing.
Common problems
Ranked by how often each turns out to be the cause for this species. Each links to a diagnosis page with the causes ranked for this species.
- Brown crispy edges monitor
- Frond drop this week
- Yellow leaves this week
Pest and disease guidance for this species consulted at the Missouri Botanical Garden Plant Finder, checked 2026-09-11.
Pests
Recorded for this species. Each links to identification and treatment.
- Scale insects this week
- Spider mites act today
Propagation
Division in soil. Roots in 21 to 42 days.
| Preferred method | division |
|---|---|
| Medium | soil |
| Time to root | 21–42 days |
| Node required | No |
| Best season | Spring and summer |
Sources
- ASPCA Animal Poison Control — Nephrolepis exalta bostoniensis Checked 2026-09-11.
- North Carolina Extension Gardener Plant Toolbox — Nephrolepis exaltata (consulted; entry exists and records no poison data.) Checked 2026-09-11.
- Wikidata entity Q136883 — taxonomy and entity identity.
- Royal Botanic Gardens Kew, Plants of the World Online — Nephrolepis exaltata Accepted name; family Polypodiaceae. Checked 2026-09-11.
- Missouri Botanical Garden Plant Finder — Nephrolepis exaltata Pest and disease guidance. Checked 2026-09-11.
- Photograph: Wikimedia Commons contributor, Wikimedia Commons , CC BY-SA 3.0.
Compiled and edited by Tony Valcarcel · 2026-09-02
Tony Valcarcel is the editor and publisher of this database, not a horticulturist
or a veterinarian. Every fact above is drawn from the sources listed, and
toxicity severity is reported only where one of them stated it.
How this is sourced.
Last updated 2026-09-02