Bird’s nest ferns are a popular houseplant known for their attractive fronds that form a rosette shape resembling a bird’s nest. However, it can be alarming when the fronds start turning brown. There are several potential causes for the browning leaves, most of which can be easily remedied with some adjustments to care. Let’s explore the most common reasons bird’s nest fern leaves turn brown and what you can do about it.
Overwatering
One of the most common reasons for browning fronds on bird’s nest ferns is overwatering. These ferns prefer evenly moist soil but not wet or saturated. When the soil remains soggy for too long, it deprives the plant’s roots of oxygen. Root rot can set in, preventing the roots from taking up water and nutrients. Subsequently, the fronds dry out and turn brown.
Here are some signs of overwatering:
- Soil stays wet for days after watering
- Roots appear dark brown or black
- Fronds are limp or drooping
- Lower fronds turn yellow or brown
To remedy this, allow the soil to dry out completely between waterings. Only water when the top inch of soil feels dry to the touch. You may need to repot the plant in fresh, well-draining soil if root rot has set in. Cut away any dead or dying fronds to improve the plant’s appearance.
How often to water a bird’s nest fern
Bird’s nest ferns should be watered only when the topsoil is partly dry. During the warm growing season, this typically means watering once a week. In the cooler winter months, you may only need to water every 10-14 days.
Always check the soil moisture before watering. Insert your finger into the soil about an inch deep—if it feels dry and crumbly, it’s time to water. Otherwise, hold off until the top inch is partly dry before watering again.
When watering, pour enough so that excess drains from the drainage holes at the bottom of the pot. This ensures the entire root zone receives moisture.
Underwatering
While overwatering is more common with bird’s nest ferns, underwatering can also cause browning fronds. If the soil dries out too much between waterings, especially during the warmer months, it puts stress on the plant. With inadequate moisture, the roots cannot absorb what they need to supply the fronds. The older fronds near the base of the plant will turn yellow or brown first when under-watered.
Signs that your plant is too dry include:
- Soil is bone dry
- Leaves appear dull, dry, or curling
- Lower leaves turn brown and crispy
To fix this, give the plant a thorough soaking to rehydrate the soil and roots. Water until it drains freely from the drainage holes. Going forward, check the soil more frequently to water before it completely dries out. The ferns prefer evenly moist soil at all times.
You may need to trim off any severely dried fronds, but otherwise, the plant should perk back up with consistent watering. Just be careful not to then overcompensate with too much water.
Ideal humidity for a bird’s nest fern
Bird’s nest ferns thrive in humid conditions between 50-70% relative humidity. Homes are often dry, especially in winter with the heater running. Use a humidifier near your fern to increase moisture in the air.
You can also set the pot on a pebble tray filled with water, which helps create a humid microclimate around the plant as the water evaporates.
Misting the fronds daily also boosts humidity. Avoid misting late in the day, as wet fronds overnight can encourage disease.
Low Humidity
Ferns naturally grow in tropical forests under shady, humid conditions. When humidity is too low, it causes excess moisture loss from the fronds. If the air stays very dry for too long, the ends may turn brown and crispy.
In addition to browning tips, signs of insufficient humidity include:
- Fronds appear dull or dry
- Leaf edges turn brown
- Fronds curl or shrivel
Boost the humidity around your plant by:
- Using a humidifier
- Placing the pot on a pebble tray
- Misting the plant daily
- Grouping plants together to increase local humidity
Trim off any excessively dried fronds if needed to improve appearance. Otherwise, correct watering and increased humidity should restore the plant’s health.
Excessive Light
Direct sun will quickly scorch the delicate fronds of bird’s nest ferns. They grow best in bright, indirect light. When light is too intense, you may notice:
- Fronds brown or yellow, starting at the tips
- Crispy, dried out appearance
- Bleached or faded color
Move the plant further away from any windows receiving direct sunlight. Sheer curtains can help filter intense light. Turn the pot regularly so all sides receive equal lighting.
If possible, provide some shade during the hottest part of the day. The north or east sides of a room generally have ideal bright, indirect light conditions.
Ideal lighting conditions for a bird’s nest fern
Bird’s nest ferns prefer bright, filtered light:
- East or west-facing window (no direct sun)
- Near a north-facing window
- Indirect outdoor shade
- Bright office or room with sheer curtains
Avoid direct southern exposure, which is usually too intense. Measure the light in the space using a light meter app on your phone. Ideal readings for a bird’s nest fern are between 200-800 foot-candles.
Drafts
Exposure to cool drafts or bursts of hot air can also cause bird’s nest fern fronds to turn brown. Ferns prefer stable temperatures between 65-80°F.
Sources of damaging drafts include:
- Leaky windows or doors
- Vents blowing air current onto the plant
- Frequently opening exterior doors
- Air conditioning or heating vents
If you notice browning fronds, assess if any drafts are reaching the plant. Move the pot away from vents and leaky areas. Avoid placing ferns near frequently opened doors leading outside.
Shield the plant from direct air flow using curtains or furniture. Maintain indoor temperatures in the ideal range for these tropical plants.
Ideal temperature range for bird’s nest ferns
Bird’s nest ferns prefer warm indoor temperatures between 65-80°F. Cooler or frequent fluctuations can stress the plant.
Keep ferns away from drafts from vents, windows and doors. Move plants away from chilly areas or hot air flows.
Avoid placing ferns in rooms that will drop below 60°F in winter. Supplement warmth with a heat source if needed to keep ideal temperatures.
Pests
Insect infestations can also contribute to browning bird’s nest fern fronds. Common pests include:
- Mealybugs – White cottony deposits on stems and leaves
- Scale – Hard brown bumps attached to fronds
- Spider mites – Webbing on underside of leaves
Inspect closely for any signs of pests like webs, bumps or cotton deposits. Remove any visible insects. For more advanced infestations, use horticultural oils or insecticidal soaps. Isolate treated plants away from other houseplants.
Pests cause plant stress, leaving ferns more vulnerable to diseases. Ensure plants get adequate sunlight, water and humidity to help withstand pest attacks. Discard any heavily infested fronds which likely cannot be salvaged.
How to inspect houseplants for pests
Follow these tips to inspect houseplants closely for signs of pests:
- Use a magnifying glass to look for tiny insects
- Check leaf undersides for webs or eggs
- Look for any cottony, sticky or waxy deposits
- Watch for honeydew drips which can indicate sap-sucking pests
- Isolate plants showing signs of pests
- Shake foliage over paper to dislodge insects
Detecting infestations early makes treatments more effective. Remove any visible insects by hand to reduce populations. Monitor closely following treatment to ensure pests are eliminated.
Fluoride
High fluoride content in water can also cause tips or edges of leaves to turn brown. Fluoride toxicity occurs when leaves absorb more fluoride than the plant can tolerate.
Signs include:
- Browning along leaf margins or tips
- Twisted, curled leaves
- Burned, dried appearance
- Lower leaves affected first
Use distilled or rainwater when possible if your tap water has high fluoride levels. Let tap water sit for 24 hours before using to allow fluoride to dissipate. Avoid fertilizers containing fluoride.
Remove any heavily damaged fronds, but the ferns can generally recover with reduced fluoride exposure. New fronds that emerge should appear greener and healthier.
Ideal EC level for bird’s nest ferns
The ideal EC (electrical conductivity) range for bird’s nest fern irrigation water is 0.5 to 0.7 mS/cm. Higher than this can cause leaf burn and tip damage over time as salts accumulate.
Here are some guidelines for EC levels:
- 0.5-0.7 mS/cm – Ideal for bird’s nest ferns
- 0.7-1.0 mS/cm – Acceptable for short periods
- 1.0+ mS/cm – Risk of frond damage increases
Use distilled or rain water if your tap water EC exceeds 0.7 mS/cm. Flushing pots monthly with distilled water can help prevent salt buildup.
Old Fronds
Bird’s nest ferns shed their lower fronds as they age. This is a natural part of the plant’s life cycle. As new fronds emerge in the center, bottom fronds turn yellow or brown before dropping off.
Do not be alarmed if older fronds regularly turn brown and fall away. Simply remove the unsightly fronds to maintain the plant’s appearance.
As long as new growth appears healthy, natural dieback of lower fronds is not problematic. It becomes a concern mainly if inner fronds start browning before the lower ones.
How to encourage new frond growth
Encourage bird’s nest ferns to produce new fronds with:
- Bright, indirect light
- Warm temperatures of 65-80°F
- Moderate fertilization in spring and summer
- High humidity around 50-70%
- Even moisture – allow soil to partly dry between waterings
New fronds generally emerge from the plant’s center. Avoid overwatering which can lead to root rot and hinder new growth.
Trim off any dead or damaged outer fronds to maintain the plant’s appearance. New growth indicates the fern is receiving proper care.
Conclusion
If your bird’s nest fern leaves are turning brown, examine how you are caring for the plant. While a few bottom fronds naturally dying off is normal, extensive leaf tip browning or dying fronds indicates a problem.
The most common causes are over or under-watering, low humidity, too much light, pests, and fluoride toxicity. Making adjustments to your care regimen, such as improving watering technique, providing better humidity, and changing the lighting can often reverse damage and restore the fern’s health. But do investigate whether pests or fluoride are causing the issue, as these require special treatment.
With proper care in the right environment, bird’s nest ferns make excellent easy care houseplants. Pay attention for any signs of distress and address them promptly by modifying how you are caring for these tropical ferns. With a little extra attention, you can get those lush green fronds looking their best in no time.
