Wouldn’t it be lovely to get a present every day? Wild petunia, a low-growing, hard-working native flower, gets you pretty close. The tissue-thin lilac-blue petals stay slightly wrinkled when they open—almost like bits of wrapping paper. And this tidy wildflower doesn’t unfurl just for your birthday. The delicate gift-wrap blooms appear on the small, shrubby, olive-green plants from May to October. Wild petunia (Ruellia humilis) is found in prairies and meadows in most of the eastern United States. Though the blossoms are gossamer, the plant itself is tough. It will adapt to most conditions, except for wet feet.
Common name: Wild petunia
Botanical name: Ruellia humilis
Plant type: Perennial
Zones: 4 to 8
Height: 1 to 2 feet
• Sun: Full sun to part shade
• Soil: Average, well drained
• Moisture: Average to dry
• Mulch: Mulch to preserve moisture in the soil.
• Pruning: None needed.
• Fertilizer: None needed.
• By seed and by division
Pests and diseases
• Vulnerable to rust, leaf spot, and root rot.
• Attracts butterflies.
• Wild petunia grows in clumps that spread slowly, but not invasively. It can also spread by seed.
• Wild petunia is small, so plant it where it won’t be overwhelmed by tall perennials. Good companions include butterfly weed, dianthus, prairie smoke, and shooting star.
• Give wild petunia a home in front of the border, where the pale lavender blooms will catch your attention.
All in the family
• Most members of the Acanthaceae family are tropical plants. A few that might be in your temperate garden are bear’s breeches (Acanthus mollis) and black-eyed Susan vine (Thunbergia alata).
Where to buy
• Shooting Star Nursery, Georgetown, KY, 866-405-7979, www.shootingstarnursery.com.
• Sweet Nectar Nursery, Battle Ground, WA, 360-624-4901, www.sweetnectarnursery.com.
• Toadshade Wildflower Farm, Frenchtown, NJ, 908-996-7500, www.toadshade.com.
(Text by Elizabeth Noll, photo courtesy of Missouri Botanical Garden’s Kemper Center for Home Gardening)