Although it may be called 4 o'Clock because it is said to bloom in the afternoon at that time, it blooms in the early morning and closes its' flowers in the heat of the afternoon. 4 o'Clocks are perennials that freeze to the ground every year here in West Florida, then in the spring new vigorous plants emerge from tubers underground.
They grow well in poor soil but appreciate the protection of shade during the dry season. They do very well in shade, but can tolerate full sun with plenty of water.
The fragrant little flowers bloom for months, and make tiny black seeds that may reseed in other parts of the garden. People have used the flowers as an edible crimson food coloring for cakes and jellies.
The tender young leaves can be eaten as cooked greens.
The root was used as a treatment for dropsy (CHF) and as some kind of hallucinogen.
Not a lot of information can be found on whether 4 o'Clocks can be used as a fodder source.