"Ruellia simplex", Britton's wild petunia, Mexican petunia, Mexican bluebell, is a species of flowering plant in the acanthus family, Acanthaceae. It is a native of Mexico, the Caribbean, and South America. It is an evergreen perennial growing 3 ft (0.91 m) tall, forming colonies of stalks with lance-shaped leaves that are 6 to 12 in (15 to 30 cm) and .5 to .75 in (1.3 to 1.9 cm) wide. Trumpet shaped flowers are metallic blue to purple, with five petals, and 3 in (7.6 cm) wide. Varieties with white, pink, and many shades of blue are available, as are dwarf versions that form clumps that are about 8-12 inch in height.