Group of shrubby perennials native to New and Old World tropics and treasured for their flowers. Bloom continuously in warm weather, with long, whiplike spikes bearing clusters of small, showy blossoms that attract butterflies and hummingbirds. Effective in naturalized areas, in mixed herbaceous borders, and when massed. Plants self-sow readily and can be weedy.
S. jamaicensis. BLUE PORTERWEED. Native to south Florida, where it is widely sold and planted. Mounding plant to 12 ft. tall and wide, with dull green, coarsely toothed, pointed-oval leaves to 3 in. long. Slender flower spikes resembling a rat's tail rise at least a foot above the foliage. Blue, 14-in. flowers appear singly or in clusters, starting at bottom of spike and proceeding upward. Individual flowers last just a day. Best in partial shade.
S. mutabilis. PINK PORTERWEED. Native to South America. Shrubby, sprawling growth to 7 ft. tall and wide. Fuzzy, light green leaves to 4 in. long are oval and pointed. Thick flower spikes rise a foot above the foliage, bearing clusters of 12-in. pink flowers that last for several days. 'Coral' is very showy, flaunting masses of coral-pink blossoms. Full sun.
S. urticifolia. NETTLELEAF VERVAIN. Native to Asia. Similar to and often confused with S. jamaicensis, but leaves are darker green and noticeably quilted on upper surface. Flowers are also slightly smaller and darker blue and have white centers. Upright, shrubby growth to 5 ft. high, not quite as wide. Individual flowers last for only a day. Full sun.