Wild Petunia
Ruellia nudiflora
Family: Acanthaceae
Perennial plant reaching about 1.5x1.5’. May go dormant in winter. Light purple flowers in warm weather.
We believe some of the wild plants we’ve seen in Arizona, like the plants in the Buenos Aires Wildlife Refuge, are a different species than the plant that is commonly sold in the trade: Ruellia ciliatiflora is an extremely similar but separate species. SEINET now lists all Arizona plants as R. ciliatiflora with R. nudiflora as a synonym, but R. nudiflora is a separate species which still may occur in Arizona.
Grow in full to part sun, moderate water, rood hardy to 10° F. Cut back as necessary. May reseed readily in the landscape.
Pollinated by numerous insects. Larval food plant for many butterflies including the following:
Malachite (Siproeta stelenes ssp. biplagiata)
Rosita Patch (Chlosyne rosita)
Pale-banded Crescent (Anthanassa tulcis)
Fritzgaertner's Flat (Celaenorrhinus fritzgaertneri)
White Peacock Anartia jatrophae
There are 370 species of Ruellia around the world usually in the tropics and subtropics. The genus was named in honor of Jean Ruelle (1474–1537), herbalist and physician to Francis I of France and translator of several works of Dioscorides. The species name, nudiflora, means "thin, slender, meager" referring to the plant's narrow leaves and delicate inflorescence.
Ruellia nudiflora is found in sandy washes and ditches:, in desert scrub and desert grassland from 1,500-4,500 ft. from Arizona to Louisiana, south through much of Mexico and Central America to Costa Rica.