Content Detail

Wild petunia is a low-growing, late spring to early fall perennial with lilac or blue flowers and light to medium green foliage. The funnel-shaped flowers attract hummingbirds, butterflies, and bees. It is a lovely addition to rock gardens, naturalized areas, beds, and borders, and it can even be planted in containers. This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region and current research.

  • Family (English) acanthus
  • Family (botanic) Acanthaceae
  • Tree or plant type Perennial
  • Native locale Chicago area, Illinois, North America
  • Size range Small plant (6-12 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Acid soil, Alkaline soil, Moist, Sandy soil, well-drained soil
  • Tolerances Alkaline soil, clay soil, Dry sites, Occasional drought
  • Season of interest late spring, early summer, midsummer, late summer, early fall
  • Flower color and fragrance Purple
  • Shape or form Mounded, Upright
  • Growth rate Moderate
  • Wildlife Birds, Butterflies, Insect pollinators

Size and method of spreading:

Wild petunia reaches a height of up to 1 foot and a spread of 1 ½ to 2 feet at maturity. It spreads by self-seeding. 

Native geographic location and habitat: (include C-value if appropriate)

Wild petunia is native to the Eastern and Central United States. C Value: 8.

Attracts birds or pollinators: 

Wild petunia attracts hummingbirds, butterflies, and bees. 

Leaf description:

Wild petunia has leaves that grow in opposite pairs along the stems. The leaves are light to medium green and hairy. They grow up to 2 to 2.5 inches long and 1 inch wide (ovate to lanceolate). The wild petunia leaves may attach to the stem directly (sessile) or may have short stalks (petioles). 

Flower description:

Wild petunia has flowers that grow individually or in small clusters from the upper leaf axils, and are typically a lilac color but can also be light blue. The flowers are individually short-lived, but the plants will continuously bloom from May to October. The flowers are funnel-shaped and have a similar shape to that of cultivated petunias. The flowers of wild petunia have a 1 ½- to 3- inch long, petallike, tubular structure (corolla) that divides into five rounded lobes at the top. Purple lines radiate around the throat of the corolla tube. Visible from inside the corolla tube are four white to purple structures in two sets of uneven pairs (didynamous stamens) with white to tan colored pollen structures on the tips (anthers). Also protruding from the corolla is another white-to-purple structure (style) with a divided tip (stigma). The constricted base of the corolla tube is surrounded by a short, hairy, leaflike tube (calyx) that divides into five long, pointed (linear) lobes at the tip.

Fruit description:

The fruit of wild petunia are smooth, dry, and split into two at maturity (capsules). They are straw-colored when ripe. When the fruit splits, it does so with so much force that the popping sound it makes is audible. The force of the splitting causes the seeds to eject, allowing the wild petunia to self-seed. 

Plant Care:

For more blooms per plant, supplemental watering is recommended.

List of pests, diseases, and tolerances:

Wild petunia is not susceptible to major pest or disease issues. Wild petunia can tolerate drought conditions and dry soils. It can also tolerate well-draining clay soils.


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