How to Keep a Fern Alive in Winter: Expert Tips

By James Wilson · January 23, 2026

To keep a fern alive in the winter, maintain consistent moisture, provide high humidity (40–60%), keep temperatures between 60–75°F (15–24°C), avoid cold drafts, and place in bright, indirect light. Reduce fertilization and monitor for pests regularly.

Why Ferns Struggle in Winter

Ferns are naturally adapted to humid, shaded forest environments. Indoor winter conditions often create a hostile environment due to:

Dry air from heating systems (humidity drops below 30%)
Cold drafts near windows or doors
Insufficient light during shorter days
Over- or under-watering due to misjudged soil moisture
Temperature fluctuations outside optimal range

Key Factors for Winter Fern Care

1. Humidity Management

Ferns require 40–60% relative humidity to thrive. Most homes drop to 20–30% in winter.

Use a humidifier near the plant
Place on a pebble tray with water
Avoid clustering too tightly with other plants to prevent mold

2. Watering Practices

Keep soil evenly moist but not soggy. Overwatering leads to root rot; underwatering causes frond browning.

Check top inch of soil weekly—water if dry
Use room-temperature water to avoid shock
Ensure pots have drainage holes

3. Light Requirements

Ferns need bright, indirect light. Direct sun scorches fronds; too little light slows growth.

East-facing windows ideal
South or west windows with sheer curtain filter
Supplement with grow lights if natural light is low

4. Temperature Stability

Maintain 60–75°F (15–24°C). Avoid placing near radiators, vents, or drafty entryways.

Sudden drops below 55°F harm most species
Consistent warmth supports metabolic activity

5. Fertilization and Feeding

Ferns grow slowly in winter and require less nutrition.

Fertilize at half strength every 6–8 weeks, or not at all
Use balanced liquid fertilizer (e.g., 10-10-10)
Flush soil monthly to prevent salt buildup

Fern Species	Min Humidity (%)	Min Temp (°F)	Light (fc)	Water Frequency (Winter)
Boston Fern (Nephrolepis exaltata)	50	60	100–200	Every 5–7 days
Maidenhair Fern (Adiantum spp.)	60	65	150–300	Every 4–6 days
Japanese Holly Fern (Cyrtomium falcatum)	40	55	100–150	Every 7–10 days
Rabbit's Foot Fern (Davallia fejeensis)	50	60	100–200	Every 6–8 days
Button Fern (Pellaea rotundifolia)	40	55	100–150	Every 7–9 days

Table data source:1, 2, 3

The table shows significant variation in humidity and temperature needs among common house ferns. Boston and Maidenhair ferns require higher humidity and warmth, making them more challenging in winter. Japanese Holly and Button ferns are more tolerant of lower humidity and cooler temps, ideal for less controlled environments.

Common Problems and Solutions

Yellowing Fronds

Often caused by overwatering or poor drainage. Ensure pot has holes and soil is well-aerated.

Brown Leaf Tips

Typically due to low humidity or inconsistent watering. Increase moisture in the air and maintain even soil hydration.

Dropping Leaves

Can result from sudden temperature changes, drafts, or underwatering. Relocate away from cold windows and check soil weekly.

Pest Infestations

Spider mites and scale thrive in dry indoor air. Inspect regularly, wipe leaves with damp cloth, and treat with insecticidal soap if needed.

Frequently Asked Questions About Keeping Ferns Alive in Winter

How often should I water my fern in winter?

Most ferns need watering every 5–10 days in winter, depending on species and home conditions. Always check the top inch of soil: if dry, it's time to water. Use room-temperature water to prevent shock.

Can I use a humidifier for my fern?

Yes, a cool-mist humidifier is one of the most effective ways to maintain 40–60% humidity. Place it near (not directly on) the fern to prevent leaf wetness and fungal issues.

Do ferns need sunlight in winter?

Ferns need bright, indirect light year-round. In winter, place near an east-facing window or supplement with a grow light for 10–12 hours daily if natural light is limited.

Why are my fern's leaves turning brown?

Brown leaves usually indicate low humidity, underwatering, or exposure to drafts. Adjust care by increasing humidity, maintaining consistent moisture, and relocating away from cold air sources.

Should I fertilize my fern in winter?

Fertilize sparingly, if at all. Use half-strength balanced liquid fertilizer every 6–8 weeks. Most ferns enter slower growth phases and excess nutrients can damage roots.