Ruellia humilis is a compact, profusely-blooming perennial that can reach up to 2', although it typically grows to a height of 1'. The leaves are oblong, up to 2" long, and covered top and bottom with fine hairs that give the foliage a silvery cast. The flowers are trumpet-shaped and petunia-like, up to 2 1/2" long, and range in color from lavender to lilac. They are produced in the upper leaf axils, forming open clusters. It has a propensity to spread, and, with its low-growing habit, can be useful to fill in gaps in the garden and when establishing a low meadow.
Wild petunia is very versatile and easy to grow. It is intolerant of wet feet and full shade, but other than that, it will grow under just about any conditions. It is a profuse bloomer, beginning in early summer and going strong through the hot, dry summer months. When grown in rich, moist soil, it can be bullied by taller and more aggressive species, so it is best planted en masse in the front of the flower bed.
Space plants 12"-18" on center.
Wild petunia spreads easily from seed. The dispersal mechanism "explodes" the seeds outward, so you may find they propagate themselves prolifically in favorable conditions. The spread can be limited by deadheading.
On the shadier side of its tolerance, wild petunia pairs well with Aquilegia canadensis (American columbine) and Polemonium reptans (Jacob's ladder), and will extend the blooming interest of the planting through the end of summer. Or, include it on the edges of a taller planting of sun lovers like Coreopsis tripteris (tall tickseed), Echinacea pallida (pale purple coneflower, Veronicastrum virginicum (Culver's root), Coreopsis tripteris (tall tickseed), Eryngium yuccifolium (button eryngo), Vernonia fasciculata (prairie ironweed), and Liatris pycnostachya (prairie blazing star). Add in Symphyotrichum laeve (smooth blue aster) to fill out a middle layer. Include a grass or two, like Schizachyrium scoparium (little bluestem), Eragrostis spectabilis (purple lovegrass), or Bouteloua curtipendula (sideoats grama).
Wild petunia is pollinated primarily by long-tongued bees. Short-tongued bees and Syrphid flies also visit to collect stray pollen.
The genus Ruellia was named by Carl Linnaeus in honor of French botanist and physician to King Francis I, Jean Ruel (1474 - 1537). Due to typographical interpretations, misidentification, and a yearning to Latinize names back in the day, he is also known as Jean Ruelle, Jean de la Ruelle, and Ioannes Ruellius (people’s names can get messy too). The specific epithet humilis, is a Latin adjective meaning low-growing, and is the root for commonly used English words such as humble and humiliate.
The common name, wild petunia, is somewhat of a misnomer. Although the flowers are similar in appearance to those of true petunias, they come from two distinct families. Ruellia humilis is a member of the Acanthus family. True petunias are in the genus Petunia and are members of the Nightshade (Solanaceae) family, which includes tomatoes.
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Would you like your plants shipped later? You may choose to do so in the shopping cart.
Note: Early spring shipments might include plants that have not yet broken dormancy, or have not been vernalized and will be frost-tender. Please use your best judgment when selecting your preferred ship week.
Did you know? When plants are available from multiple growers, we list growers closest to your location first.
Why choose plants from the nearest grower? Choosing a the grower closest to you makes it more likely the plants are consistent with your ecoregion and better adapted to your location. In addition, shipping plants shorter distances typically uses fewer resources, something we can all get behind!
Recorded County Distribution: USDA data.
AL, AR, GA, IA, IL, IN, KS, KY, MD, MI, MN, MO, MS, NC, NE, OH, OK, PA, TN, VA, WI, WV, FL, LA, TX |
Endangered | MD, PA, WI |
Threatened | MI, NC |
Atlantic and Gulf Coastal Plain | FACU |
Eastern Mountains and Piedmont | FACU |
Great Plains | FAC |
Midwest | FACU |
Northcentral and Northeast | FACU |
MAP OF WETLAND DELINEATION REGIONS
Code |
Status |
Designation |
Comment |
OBL |
Obligate Wetland |
Hydrophyte |
Almost always occur in wetlands |
FACW |
Facultative Wetland |
Hydrophyte |
Usually occur in wetlands, but may occur in non-wetlands |
FAC |
Facultative |
Hydrophyte |
Occur in wetlands and non-wetlands |
FACU |
Facultative Upland |
Nonhydrophyte |
Usually occur in non-wetlands, but may occur in wetlands |
UPL |
Obligate Upland |
Nonhydrophyte |
Almost never occur in wetlands |
Kingdom | Plantae | Plants |
Subkingdom | Tracheobionta | Vascular plants |
Superdivision | Spermatophyta | Seed plants |
Division | Magnoliophyta | Flowering plants |
Class | Magnoliopsida | Dicotyledons |
Subclass | Asteridae | |
Order | Scrophulariales | |
Family | Acanthaceae | Acanthus family |
Genus | Ruellia | wild petunia |
Species | Ruellia humilis | wild petunia |
fringed wild petunia, hairy wild-petunia, hairy ruellia, low wild-petunia, fringed-leaved petunia, prairie petunia, low ruellia, fringeleaf wild petunia
Ruellia ciliosa var. longiflora
Ruellia humilis var. calvescens
Ruellia humilis var. depauperata
Ruellia humilis var. expansa
Ruellia humilis var. frondosa
Ruellia humilis var. longiflora
Sizes info
Shipping is free on all plants orders!
Your plants will ship using each grower’s preferred method: FedEx Ground, UPS Ground, or Spee-Dee Ground (in select midwestern states). Our growers ship orders Monday through Wednesday. The farther your plants need to travel, the earlier in the week they will ship. The goal is to have all plants delivered by the end of the week.
Shipping plugs:
Plugs are shipped in full flats, sometimes also referred to as trays. Multiple flats can be shipped in a single box. The flats are wrapped in netting or craft paper to secure the plants, and spacers are used between flats to keep the plants from being crushed.
When you unpack your plugs, the plants will have been somewhat flattened by the netting or craft paper. They will straighten out within a couple of days. You may also gently “fluff” them a bit to speed up the process. In some cases, your plants might have been cut back before packing, if the grower deemed them to have become too tall for safe packaging. Don’t worry, though, these guys know what they’re doing and would not compromise the health of the plants. They’ll fill back in in no time.
After receiving your plants’ journey in a dark box, it will be important to acclimate them to sunlight again. Over a couple of days, you should gradually move them into their preferred light exposure, and water them as per their requirement.
Although we always recommend putting your plants in the ground as soon as possible, they can stay healthy in the flats for a considerable amount of time. The key is to respect their growing requirements: if the species requires full sun, do not store them in the shade. If it is best adapted to dry soil, do not over-water.
Planting plugs:
We consider plugs ready to ship when the plants’ roots have filled the entire liner cell and the plants can easily be pulled out. In some cases you will have to go about it gently, wiggling the plant by the crown, and possibly squeezing the bottom of the liner to compress the growing medium and release the roots. Other times, the plants will appear to be root bound. They are not in the traditional sense. The plants are healthy but they have used up all the growing medium available to them. Plugs are at an aggressive stage of growth. As soon as planted the roots will immediately expand into your native soil. They establish faster than plants in larger containers, because they don’t have the luxury of a lot of growing media that can inhibit the roots from venturing outside of their comfort zone.
We are not going to address area preparation because the process can be complex and is always site-specific. However, as a rule, we recommend disturbing the soil as little as possible, and we do not recommend amending the soil. If you chose the right plant for the right conditions they will thrive. Any disturbance and amendments will only encourage weeds to emerge that never had a chance to do so before.
Installing plugs cannot be easier: dig a hole large enough for the roots to fit snugly inside, then water them in to eliminate air gaps. We recommend using a soil knife, sometimes referred to as hori hori, or a drill-adapted auger if it’s a large installation. If you use an auger, you will need a powerful drill. Depending on the size of the project and the type of soil, the process can be beyond what an average drill will bear. Mulching is recommended after installation to help keep weeds down while the plants establish. Be sure to keep it away from the crown of the plants. For large projects, you may want to mulch the area before planting, rather than tiptoeing through it after the fact. As a side note: if you are installing plugs in the fall, you might want to plant them so that the crown is about ¾” lower than the surrounding soil. The winter’s freeze/thaw cycles can push plugs out if the roots did not have enough time to establish and anchor them in.