Nyctinastic Movement on oxalis triangularis
What's Happening
Oxalis triangularis exhibits nyctinastic movement (leaf folding at night) regulated by a circadian clock system involving hormone signaling and calcium ion flux. Research demonstrates that leaflets fold upward along the midrib during darkness through differential cell expansion in pulvini (swollen leaf bases), driven by rhythmic changes in potassium and chloride ion transport. This movement is not merely mechanical but involves complex circadian regulation that synchronizes with light-dark cycles.
How to Fix It
- 1
Provide bright indirect light during day hours to support robust circadian cycling
- 2
Avoid disturbing the plant during evening hours when leaves begin folding (typically 1-2 hours before darkness)
- 3
Maintain temperatures between 65-75°F (18-24°C) as temperature extremes can disrupt nyctinastic timing
- 4
Do not mistake evening leaf folding for wilting or distress—this is normal behavior
How to Prevent It
Maintain consistent light-dark cycles (12-14 hours light) to support healthy circadian rhythms. Avoid irregular lighting schedules or placing plants in areas with artificial light at night, which disrupts the natural folding cycle.