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Wild Petunia
Ruellia humilis

Family: Acanthaceae (ah-kanth-AY-see-ee) (Info)
Genus: Ruellia (roo-EL-ee-uh) (Info)
Species: humilis (HEW-mil-is) (Info)
View this plant in a garden

Category:

Perennials

Height:

6-12 in. (15-30 cm)

Spacing:

18-24 in. (45-60 cm)

Hardiness:

USDA Zone 3a: to -39.9 C (-40 F)

USDA Zone 3b: to -37.2 C (-35 F)

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Partial to Full Shade

Danger:

N/A

Bloom Color:

Violet/Lavender

Bloom Time:

Mid Summer

Late Summer/Early Fall

Foliage:

Herbaceous

Other details:

Drought-tolerant; suitable for xeriscaping

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:

Non-patented

Propagation Methods:

From seed; direct sow outdoors in fall

Seed Collecting:

Bag seedheads to capture ripening seed

Allow pods to dry on plant; break open to collect seeds

Regional

This plant has been said to grow in the following regions:

Huntington, Arkansas

Deland, Florida

Green Cove Springs, Florida

Keystone Heights, Florida

Umatilla, Florida

Zephyrhills, Florida

Cornelia, Georgia

Demorest, Georgia

Chicago, Illinois

Hampton, Illinois

Lincoln, Illinois

Wichita, Kansas

Taylorsville, Kentucky

Dracut, Massachusetts

Hopkins, Minnesota

Minneapolis, Minnesota

Saint Paul, Minnesota

Mathiston, Mississippi

Belton, Missouri

Cole Camp, Missouri

Saint Louis, Missouri

Frenchtown, New Jersey

Elizabeth City, North Carolina

Columbus, Ohio

Ney, Ohio

Sawyer, Oklahoma

New Hope, Pennsylvania

Villanova, Pennsylvania

Beaufort, South Carolina

Conway, South Carolina

Saint Helena Island, South Carolina

Murfreesboro, Tennessee

Alice, Texas

Arlington, Texas

Austin, Texas

De Leon, Texas

Georgetown, Texas

Houston, Texas

Lipan, Texas

Leesburg, Virginia

Appleton, Wisconsin

show all

Gardeners' Notes:

5
positives
5
neutrals
1
negative
RatingContent
Positive

On Feb 6, 2014, Rickwebb from Downingtown, PA wrote:

A really nice native plant of American meadows and prairie in the East and Midwest. I've seen it in native, naturalistic landscapes in Illinois and Wisconsin.

Neutral

On Nov 27, 2012, ms_greenjeans from Hopkins, MN (Zone 4a) wrote:

I was intrigued by the idea of a perennial petunia. I planted a couple and have had them now for a few years. They are very low maintenance and they're beautiful when they bloom. I do wish they had a longer bloom period, however.
Update summer 2013: After not doing a lot for the first two years I had it, these have taken off this summer. I have quite a clump of them now and they are blooming. Very pretty!

Neutral

On Aug 4, 2011, TheOldME from San Antonio, TX wrote:

This plant is found mostly in the cracks and crevices around the patio and walkways. It's a nice plant - just appears in inconvenient places. I was spraying some Roundup on some grass and sprayed some on a few of the (believed to be) wild petunias. In a few seconds I started hearing some very noticeable popping sounds. At first I thought it was some sort of snapping bug or grasshoppers that the spray had irritated. Something was even hitting me and it was ricocheting off of things nearby. When I looked closely I found that the seed pods on this plant were popping open and ejecting a seed. They were traveling several feet. I assume that the moisture in the spray must have made the plant react as if to rain and thus spread its seeds. I have not seen this interesting feature reported... read more

Positive

On Jun 15, 2011, appublic from Belton, MO (Zone 5b) wrote:

This is a tough plant! I grew mine from seed last year and I wasn't good about watering them when the second half of our summer was unusually dry. They toughed it out for a long time, but eventually withered away and, I thought, died. I was mad at myself because I really liked them and resolved to grow more for this year, which I did. I was stunned to discover that they returned this spring and I'm happy I have my new plants to add to last year's. I should note that even as first year perennials they bloomed. That they also survived my lack of care and returned tells you how tough they are.

Positive

On Jun 16, 2010, PammiePi from Green Cove Springs, FL wrote:

This is a pretty plant which grows wild on the edges of the woods and pops up here and there in the lawn with it's pretty "burple" flowers. I have a few volunteers I treat with extra care, and these are growing well & flowering non-stop. They remind me, in form & looks, of another plant I have, "Blue Bells" Browallia. These plants apparently seed, and also tolerate high humidity & temperatures, as well as frost. They also are drought-tolerant. They grow in the sandy, dry, shaded mixed wooded edges as well as out in the full sun where I live.

Neutral

On Nov 4, 2009, grrrlgeek from Grayslake, IL (Zone 5a) wrote:

Native in the US from TX to MN, east to PA, south to FL. Endangered in MD, PA, and WI, threatened in NC and MI.

Negative

On Mar 11, 2009, cam2 from Houston, TX wrote:

This is a noxious evergreen weed in my yard ~ I fight it in every flowerbed and between bricks on the patio! It is pretty in bloom and the foliage is nice; if it were just more easily controlled.

Positive

On Nov 30, 2006, frostweed from Josephine, Arlington, TX (Zone 8a) wrote:

Wild Petunia Ruellia humilis is native to Texas and other States.

Neutral

On Nov 12, 2003, Gamblemoore1987 from St. Louis, MO (Zone 6a) wrote:

In St. Louis this reseeds but does not last the winter. Hardy, warm season, full sun, annual.

Positive

On Aug 31, 2002, Terry from Murfreesboro, TN (Zone 7a) wrote:

Talk about an easy-to-grow plant. This grows wild in the cow pasture behind our property. The blooms don't have the staying power of the annual petunias but the fact it's a perennial and virtually care-free make up for the lack of profuse blooms.

Neutral

On Aug 8, 2001, talinum from Kearney, NE (Zone 5a) wrote:

Low spreading perennial for dry shade. Misty lavender miniature petunia-shaped blooms throughout summer. Flowers slightly more than 1" acoss. Prefers high heat and humidity. Will reseed occasionally.