An underwatered bird of paradise plant leaves turn yellow and brown and appear dry at the edges. The leaves wilt, and the plant grows slower than usual.
The bird of paradise does not only curl its leaves when underwatered but also when overwatered. When excessively watered, the plant develops root rot disease.
Lower winter temperatures freeze the roots and stems, preventing them from absorbing and transporting water to the leaves and other parts.
The Strelitzia plant prefers locations with higher humidity of 60-80 to thrive. It curls its leaves in low humidity areas.
Bird of paradise thrives in temperatures of 65oF to 85oF. In higher temperatures, it curls its leaves upwards or downwards.
When sap-sucking species such as spider mites, mealybug, scales, and thrips invade bird of paradise, they make the plant curl its leaves.
When placed in direct sunlight longer, the leaves curl inwards. Too much direct sunlight makes the plant lose water faster. Therefore, it closes its leaves to reduce its surface area.
Potting, transplanting, or moving the plant to a different location shocks it, which is why it gets curled leaves.