Mexican petunia (Ruellia simplex) is an evergreen herbaceous perennial recognized by its wrinkly, trumpet-shaped purple flowers. It is commonly cultivated as an ornamental plant. Due to its vigorous spreading ability, Ruellia simplex has become widely naturalized outside Mexico. It is considered an invasive species in many countries.

Monkey plant (Ruellia makoyana) is an evergreen perennial plant that will grow from 30 to 61 cm tall and 46 cm wide. It has white-veined, velvety leaves with flashy purple undersides. It blooms from summer to fall with pink, trumpet-shaped flowers. Makes a beautiful ground cover for shaded areas. Drought-tolerant but not frost-tolerant.

Tropical wild petunia is often grown as a houseplant. In its native habitat, this plant grows under the canopy of tall trees, making it well adapted to indoor, low-light conditions. The small, delicate flowers are pretty and bloom often.

Carolina wild petunia (Ruellia caroliniensis) is a wild flowering petunia species native to the southeastern United States like South Carolina, Florida, Alabama, and Louisiana. It is planted ornamentally for its attractive flowers.

Native to eastern and central United States the wild petunia (Ruellia humilis) is more and more popular among local gardens as a native flowering plant. Its leaves and stem are hairy. Tubular petunia-like flows appear singly or in clusters during its spring to fall bloom period.

Violet wild petunia (Ruellia nudiflora) is a flowering perennial plant native to the Sonoran Desert region of North America. While the common name violet wild petunia uses the word petunia, this plant is not scientifically classified as a true petunia.

Wild Petunia (Ruellia strepens) is a perennial wildflower commonly found in woodland areas and growing along streams. It produces showy lavender-blue trumpet-shaped flowers from spring through summer attracting butterflies and hummingbirds to its nectar. It is drought tolerant.

Red ruellia (Ruellia elegans) is often used in pollinator gardens, as its scarlet flower show is loved by butterflies and hummingbirds. Since it's so eye-catching and deer resistant, it's also used in landscaping for beds, borders, and patio decoration. It's technically an annual plant, but since it reseeds easily and spread quickly, some actually consider it a perennial.

If you combine some damp soil and warm temperatures, you'll find the perfect growing environment for minnieroot (Ruellia tuberosa). Wild growth can become almost uncontrollably weedy, but that's great for pollinators. Hummingbirds, in particular, love their long, tubular flower throat.

Ruellia blechum, also known as browne's blechum, is an annual or perennial herb native to Mexico and northern South America. It grows to less than 50 cm tall with erect flower shoots and opposite, ovate, stalked leaves 2 to 7 cm long. The flowers are white or purple and arranged in dense spikes that appear squarish because of floral bracts. The fruit is an ellipsoid capsule with 2 brown circular seeds. This plant has spread to warmer places around the globe, including much of the Pacific and parts of Asia and Australia, through the ornamental plant trade. Unfortunately, it has also escaped into the wild and become something of a weedy pest. Nevertheless, Ruellia blechum is still a popular ornamental plant due to its attractive flowers and easy care requirements.

Dipteracanthus 'Elastica' is named for its attractive bubble-shaped leaves, which look like they have been stretched elastically. It is these dense evergreen leaves that give this plant its ornamental appeal. Since it isn’t frost-hardy, bubble plant is most commonly grown as a houseplant. Its trailing growth makes it a popular hanging plant.

Creeping ruellia lives in East Asia in disturbed soils and open fields. It has adapted well to cities and can often be found in urban zones. Creeping ruellia is one of the few species of plants that serve as hosts to the chocolate pansy butterfly's caterpillars.