En EspaŅol

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?

Share

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Tuesday - July 17, 2007

From: Paris, France
Region: Other
Topic: Non-Natives
Title: Care of Rio Grande Wild Petunia
Answered by: Barbara Medford and Joe Marcus

QUESTION:

I have bought the Rio Grande Wild Petunia, Ruellia davisiorum. How should I look after it?

ANSWER:

The really wonderful thing about planting native plants is that they are going to be easier to care for because they are already adapted to the environment. However, while this plant is native to our Central Texas environment, we note your question came from France, so in your case, it is a non-native and may require some special provisions for it to flourish. France, like Texas, covers a wide area and includes many divergent climates, soils, elevations and ecologies.

We would hate it if any of the native plants that are so dear to us here in Texas became nuisance, or worse, invasive species in Europe. So we ask that you take particular care to make sure that your Ruellia does not escape from cultivation.

Since we don't know which area of France you may be gardening in, we can only give you the information on where Ruellia davisiorum (Rio Grande wild petunia) occurs naturally and tell you a little about the conditions there. This plant occurs naturally only in extreme South Texas and in adjacent Mexico. The "wild petunia" in the name refers to the fact that the blooms of all ruellias resemble those of Petunia, a genus of South American natives much-hybridized to produce plants of nearly every color but orange. Petunias are not closely related to ruellias.

The environment in Rio Grande Wild Petunia's native territory is generally desert shrub savannah. Soils are dark, calcareous stony clay and clay loams. Altitudes average about 2500 ft. above sea level, and temperatures average from 35 degrees in January to 97 degrees in July. Average rainfall is 17 inches a year.

Just because the native range of Ruellia davisiorum is relatively quite small doesn't mean it's the only place it will grow. There are a number of different types of ruellias, and all are pretty tough and adaptable. For example, Ruellia occidentalis (western wild petunia), is native to larger parts of Texas and therefore not quite such severe conditions. Native habitats of ruellias generally are dry, rocky woods, chapparral hills and flats on the Edwards Plateau and the Rio Grande plains. They are perennials plants. Their light requirements are light shade to shade, but in an area where the sun isn't quite as fierce as it is in Texas, they can probably tolerate more sun. Ruellias' growth habit is as an herb or a subshrub, the soil moisture can be moist or dry, and they are heat and cold tolerant.

We hope this has given you enough information to transform some of your garden into a "little bit of Texas." Best wishes.

 

From the Image Gallery


Rio grande wild petunia
Ruellia davisiorum

Western wild petunia
Ruellia occidentalis

More Non-Natives Questions

Beans growing under artificial light from Vernon CT
May 04, 2012 - What bean plant will grow the best under a flourescent,spot gro light,green transparent light,or Natural light and why.What caused it to grow like it did?
view the full question and answer

Failure to thrive of non-native Confederate Jasmine in Tucson AZ
May 27, 2010 - My Star/Confederate Jasmine, a 30 foot long wall of it, for over 5 years now has one side of it losing leaves. I seem to remember it did this one other summer, but came back in?? What could be the pr...
view the full question and answer

Planting onions in Michigan
July 30, 2009 - Hello, I live in Mi in zone 5. Can I plant green onions now (7/30/09)? And will they have enough time to have for an October-ish harvast? Thanks
view the full question and answer

Slow flowering wisteria
May 09, 2007 - We have a young wisteria growing on the side of the house. It began to flower this year for the first time. Whereas my neighbors' wisterias all bloomed in February, ours has only begun to bloom in mi...
view the full question and answer

Conflict between non-native and invasive St. Augustine and Bermuda grasses
July 21, 2008 - Mr. Smarty Plants, My neighbor and I have nice front lawns but his is St. Augustine and mine is Bermuda. Between our houses the two lawns meet and it is a constant battle to keep his St. Augustine...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center