The flowers usually open from late afternoon or at dusk (namely between 4 and 8 o'clock), giving rise to one of its common names. Flowers then produce a strong, sweet-smelling fragrance throughout the night, then close for good in the morning. New flowers open the following day.

Flowers are yellow, pink and white, but a different combination of flowers can grow on the same plant. It has color-changing properties, for example, as the plant matures, the yellow flowers can gradually change to a dark pink color. Similarly, white flowers can change to light violet.