Mirabilis nyctaginea is a species of flowering plant in the four o'clock family known by several common names, including wild four o'clock, heartleaf four o'clock, and heartleaf umbrella wort. Four-o'-clock is native to the central section of North America, and it occurs elsewhere as an introduced species, including parts of Europe. Its exact native range is obscure, and it is often weedy throughout its range, spreading into disturbed habitat easily.