phlox

a genus of perennial and, less commonly, annual herbs and sometimes subshrubs of the family Polemoniaceae. The erect or climbing stems are only slightly branching. The entire leaves are lanceolate or narrowly ovate; they are opposite except at the upper part of the stems, where they are alternate. In species with procumbent, highly branched stems that form mats, the leaves are linear or subulate; on sterile shoots the leaves are agglomerate. The flowers are in many-flowered terminal inflorescences known as thyrses; less commonly, they are solitary. The corolla has a narrow tube and a wheel-shaped, saucer-shaped, or stellate five-parted lip. The fruit is a three-valved capsule.

There are about 60 species of phlox, distributed in North America. The USSR has one spreading mountain species— P. sibirica. Many species are ornamental. One of the best-known tall-growing perennial species is P. paniculata, which has an enormous number of varieties that differ in height, shape, and size of the inflorescences and size and coloring of the flowers. The most common spreading species include P. subulata and P. setacea, and the best-known annuals include P. drummondii. In floriculture, hybrids developed with other species of Phlox are also used.