En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer
3 ratings

Sunday - June 15, 2008

From: Austin, TX
Region: Southwest
Topic: Invasive Plants
Title: Invasiveness of wild petunia in Austin
Answered by: Barbara Medford


Is the wild petunia in the data base as invasive/aggressive as the more common ruellia? In other words, will it pop up everywhere? Ruellia nudiflora (Engelm. & Gray) Urban Common wild petunia, Violet ruellia, Violet wild petunia, Wild petunia


There are four members of the genus Ruellia that are native to Texas: Ruellia nudiflora (violet wild petunia), Ruellia drummondiana (Drummond's wild petunia), Ruellia humilis (fringeleaf wild petunia). and Ruellia occidentalis (western wild petunia). All are considered Plantwise native alternatives to non-native Ruellia caerulea (Britton's wild petunia), also known as Ruellia x brittoniana "Katie", which is widely available commercially. Ruellia caerulea is on the Texas Invasives list, but whether it is more or less invasive than the natives is a little hard to say. They all seed prolifically, grow well in shady, moist areas, and grow fairly quickly in the warm season. However, information in our Native Plant Database indicates that the Ruellias can be kept under control by mowing. They are all difficult to pull up, because they have a large knot in the root just below the surface of the soil. Many gardeners pick the non-native caerulea because it has been hybridized or selected to provide other colors than the native purple; pink, white and blue, although purple has remained the most popular color. Perhaps the main point in favor of using the natives is that they ARE natives, accustomed to living in their environment, requiring less fertilizer, water and maintenance to do well.

Pictures of non-native Ruellia caerulea

Ruellia nudiflora

Ruellia drummondiana

Ruellia humilis

Ruellia occidentalis




More Invasive Plants Questions

Runaway Agave Americana from Pacific Palisades CA
April 29, 2013 - We live near open space on Santa Monica Mountain State Park. Our Association planted non-native, invasive Agave Americanas all over the adjacent slopes, and we are trying to get the exploding pups and...
view the full question and answer

Introduction of King Ranch bluestem (Bothriochloa ischaemem)
August 04, 2008 - Hello, I am a graduate student from TAMUK and I'm writing my thesis concerning natives vs. Old World Bluestems. I was wondering if you could help me find a source that states: King Ranch (or KR) Blu...
view the full question and answer

Death of non-native eleaegnus from Austin
March 30, 2013 - We have a long hedge of elaeagnus, about 5 ft tall. Four of them died in the middle of the hedge. Where can we find such big plants? Is it advisable to unroot and transplant from another area?
view the full question and answer

Distinguishing native Celastrus scandens from non-native C. Orbiculatus from Lexington MA
June 08, 2014 - Dear Mr. Plants, I maintain a wildflower garden with the Lexington Field and Garden Club in Lexington, Massachusetts. Every year, I pull up sprouts of Celastris orbiulatis. I want to plan...
view the full question and answer

Will native plants become invasive from Grapevine TX
February 23, 2013 - Main Question - I want to convert my front and back yards into a native plant sanctuary but worry about if these plants growing out of control/invasive and if neighbors will complain about these "wee...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center