four-o'clock

Ornamental perennial plant (Mirabilis jalapa; family Nyctaginaceae), also called marvel-of-Peru or beauty-of-the-night, native to the tropical New World. It is a quick-growing species up to 3 ft (1 m) tall, with oval leaves on short leafstalks. The stems are swollen at the joints. The plant is called four-o'clock because its flowers, which vary from white and yellow to shades of pink and red, sometimes streaked and mottled, open in late afternoon (and close by morning).

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