All baobab trees have flowers that open at night and fall within 24 hours. The species commonly known as African baobab ('Adansonia digitata') has large, white flowers. Each flower's round, thick petals surround a mass of purplish stamens.

The flowers open around dusk; opening so quickly that movement can be detected by the naked eye and are faded by the next morning. The fruits are large, oval to round and berry-like and hold kidney-shaped seeds in a dry, pulpy matrix. Flowers may remain attached to the trees for several days, but the reproductive phase is very short, with pollen shed during the first night and stigmas shriveled by the morning.

The African baobab is among the most long-lived of vascular plants and have large flowers that are reproductive for a maximum of 15 hours.

More Info: en.wikipedia.org