When autumn comes, the pleiones 'leaves succumb to the frosts and gradually turn yellow. "Their biological clock is tuned to the seasons. There's a precise timing to when they flower, when their leaves grow and when their leaves fall-they're never late," says Cheng Mei-li.
入秋後，一葉蘭葉片不耐秋霜侵襲，陸續轉黃，「它們的生理時鐘隨著季節調整，何時開花、長葉、落葉都有一定時序，從不遲到，」鄭美麗說。