Carolina Wild Petunia

Ruellia caroliniensis

Other common name(s):

Family:

Acanthaceae (Acanthus Family)

Plant Ecoregion Distribution Map

This map uses data from the US EPA. EPA  servers have been offline frequently so maps may not display. We are working on a solution.

Gulf Coast Prairies and Marshes, Western Gulf Coastal Plain
Northern Humid Gulf Coastal Prairies
Flatwoods, Floodplains and Low Terraces3, Pleistocene Fluvial Terraces, Red River Bottomlands, Southern Tertiary Uplands, Tertiary Uplands

Plant Characteristics

Growth Form

Herbaceous

Height

2
to
3
ft.

Spread

1
to
2
ft.

Leaf Retention

Deciduous

Lifespan

Perennial

Habitat and Care Requirements

Soil Type(s)

Sand, Clay, Well Drained, Moist, Dry

Light Requirement

Sun, Part Shade

Water Requirement

Medium

Native Habitat

Grassland, Woodland

Bloom and Attraction

Bloom Color

Pink, Purple

Bloom Season

Summer

Seasonal Interest

Seeds, Nectar, Pollen, Larval Host

Wildlife Benefit

Butterflies, Birds, Moths, Bees

Maintenance

Landscape use includes groundcover, hanging baskets, patio containers, prairie meadows, pollinator gardens. Will grow in a variety of soils. NSeeds explode off the plant when ripe, so little volunteers pop up nicely around the garden. Native habitat: on dry, sandy open wooded slopes, and in prairie habitats.

Comments

Blooms June-August. Clump forming. Low growing, hairy stems, with crowded, oval leaves. Produces trumpet-shaped flowers with five petal-like lobes, in axillary clusters of 2-4. The fruit is a brown capsule. Larval host: Common Buckeye butterfly.
Material Treatment Method Collection References
Seed No Treatment Seeds may be planted immediately after collection or stored and sown in spring. Germination is low. Seedlings should be given protection until the second year. Capsules change from yellow to green to brown over a 2 month period following flowering. A mature capsule is smooth and 1/2 in. long. Be sure to monitor closely as capsules dehisce mature seeds. Store seeds dry in an airtight, refrigerated container. https://www.wildflower.org/plants/result.php?id_plant=RUCA4

About the Region

Fall Symposium 2025 Logo - Teach for the Future

Salado, the location of our Fall 2025 Symposium, lies at the intersection of two ecoregions: the Edwards Plateau (Limestone Cut Plain) and Blackland Prairie (Northern Blackland Prairie).

The Edwards Plateau area is also called the Hill Country; however, this general term covers a much larger area extending farther north. Spring-fed creeks are found throughout the region; deep limestone canyons, rivers, and lakes (reservoirs) are common. Ashe juniper is perhaps the most common woody species found throughout the region. Additional woody species include various species of oak, with live oak (Quercus fusiformis) being the most common. Sycamores (Platanus occidentalis) and bald cypress (Taxodium distichum) border waterways. This area is well known for its spring wildflower displays, though they may be viewed in spring, late summer, and fall, as well. According to Texas Parks and Wildlife, average annual rainfall in the Edwards Plateau ranges from 15 to 34 inches.

The Blackland Prairie extends from the Red River south to San Antonio, bordered on the west by the Edwards Plateau and the Cross Timbers, and on the east by the Post Oak Savannah. Annual rainfall averages 30 to 40 inches, with higher averages to the east. This region is dominated by prairie species. The most common grass species include little bluestem (Schizachyrium scoparium) and Indian grass (Sorghastrum nutans) in the uplands and switchgrass (Panicum virgatum) in the riparian areas and drainages. Common herbaceous flowering plants include salvias, penstemons, and silphiums. This area has suffered greatly from overgrazing and agricultural use. Few intact areas remain, though many of the plants can be found along county roadsides throughout the region.

Our fall Symposium host chapter, the Tonkawa Chapter, includes both of these ecoregions.

Source: Wildflowers of Texas by Michael Eason