Plant genus ( Verbena ) that contains about 250 species, almost all of them native to the New World tropics and subtropics.
Two species are indigenous to the Old World. The familiar garden verbena ( V. hortensis , or V. hybrida ) is a creeping plant that has square stems and bears flat heads of phloxlike flowers, in a wide range of colours. Many U.S. species of Verbena are low-growing, small-flowered, somewhat weedy plants more commonly called vervains. The shrub lemon verbena ( Aloysia triphylla ), notable for its fragrant oil, is a member of the verbena, or vervain, family (family Verbenaceae), which contains more than 2,600 species in about 100 genera. Members of the family have opposite or whorled leaves that are usually undivided. The flowers, in spikes or clusters, usually consist of a tube flaring into four or five almost equally cut lobes. The family also includes teak .