Why Is My Calathea Leaves Curling and Turning Brown?

By Emma Johnson · January 24, 2026

Calathea leaves curl and turn brown primarily due to improper watering, low humidity, or exposure to direct sunlight. These tropical plants require consistent moisture, high humidity (60–80%), and indirect light. Other causes include over-fertilization, poor water quality, pests, or temperature stress. Correcting environmental conditions usually restores plant health.

Why Are My Calathea Leaves Curling and Turning Brown?

Calatheas are prized for their striking foliage, but curled and brown-edged leaves are common issues among indoor growers. These symptoms signal environmental or cultural stress. Understanding the root cause is key to reviving your plant.

Common Causes of Curling and Browning Calathea Leaves

Several factors can lead to leaf deformation and discoloration in Calathea. Below are the most frequent culprits:

Inconsistent watering: Both underwatering and overwatering disrupt moisture balance.
Low humidity: Calatheas thrive in 60–80% humidity; levels below 40% cause leaf edges to brown.
Direct sunlight: Harsh light scorches leaves, leading to curling and browning.
Poor water quality: Chlorine, fluoride, or mineral buildup in tap water damages sensitive foliage.
Temperature fluctuations: Cold drafts or sudden temperature changes stress the plant.
Fertilizer burn: Excess salts from over-fertilizing damage roots and leaves.
Pests: Spider mites, thrips, or mealybugs feed on sap, causing distortion and necrosis.

Diagnosing the Problem: Key Symptoms and Solutions

1. Underwatering vs. Overwatering

Dry, crispy brown edges with inward curling suggest underwatering. Conversely, yellowing with brown, mushy spots may indicate root rot from overwatering.

2. Humidity Deficiency

Brown leaf margins, especially in winter, often point to dry air. Calatheas originate from tropical understories and need humid environments.

3. Light Stress

Direct sun causes bleaching, curling, and brown patches. Place your Calathea in bright, indirect light, such as near a north-facing window.

4. Water Quality Issues

Use filtered, distilled, or rainwater if your tap water is high in minerals or chemicals. Let tap water sit out overnight to allow chlorine to evaporate.

Symptom	Most Likely Cause	Recommended Fix
Curling + dry brown tips	Low humidity or underwatering	Increase humidity to 65%; water when top inch of soil is dry
Brown patches + leaf drop	Overwatering / root rot	Allow soil to dry slightly; repot if roots are black/mushy
Yellow-brown edges + curling	Chemical burn (fluoride/chlorine)	Switch to filtered or rainwater
Leaves curling upward during day	Natural nyctinasty (normal)	No action needed
Fine webbing + stippling	Spider mites	Treat with insecticidal soap; increase humidity

Table data source:1, 2, 3

The table above correlates common Calathea symptoms with likely causes and targeted fixes. Notably, humidity and water quality appear in over 70% of reported cases, underscoring their importance in care. Proper diagnosis prevents misapplication of treatments, such as watering a plant already suffering from root rot.

How to Prevent Leaf Curl and Browning

Maintain humidity: Use a humidifier, pebble tray, or group plants together.
Water properly: Use room-temperature, filtered water and keep soil consistently moist but not soggy.
Provide ideal light: Bright, indirect light is best; avoid direct sun.
Fertilize lightly: Feed monthly in growing season (spring–summer) with diluted balanced fertilizer.
Monitor for pests: Inspect leaves regularly, especially undersides.

Common Questions About Calathea Leaf Problems

Why are my Calathea leaves curling at night?

This is normal behavior called nyctinasty. Calathea leaves naturally rise and curl at night to conserve moisture and reopen in the morning.

Can I cut off brown Calathea leaves?

Yes, you can trim severely damaged leaves with clean scissors. However, address the underlying cause first to prevent further damage.

How often should I water my Calathea?

Water when the top inch of soil feels dry, typically every 7–10 days. Frequency depends on light, humidity, and pot size.

Is tap water safe for Calatheas?

Not always. If your tap water contains chlorine, fluoride, or high minerals, use filtered, distilled, or rainwater to prevent tip burn.

How do I increase humidity for my Calathea?

Use a humidifier, place the plant on a pebble tray with water, or group it with other plants. Avoid misting alone, as it provides only temporary relief.

Conclusion

Calathea leaf curl and browning are early warning signs of environmental stress. By maintaining proper humidity, watering correctly, and using clean water, most issues can be prevented. Regular observation and prompt adjustments ensure your Calathea remains lush and vibrant year-round.