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

Sunday - March 24, 2013

From: St. Augustine, FL
Region: Southeast
Topic: Invasive Plants, Non-Natives, Herbs/Forbs, Trees
Title: Will non-native and invasive Mexican petunias grow under oak trees from St. Augustine FL
Answered by: Barbara Medford

QUESTION:

Will Mexican Petunias grow under an Oak tree?

ANSWER:

The Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants. recommends only plants native not only to North America (excluding Mexico) but to those areas in which the plants will be grown; in your case St. Johns County on the northeastern Florida coast.  Ruellia brittonia (Mexican petunia) is native to, well, Mexico. Since you live in Florida you should read the following two articles:

Floridata Ruellia brittoniana, see the Warning at the bottom of the article.

Florida Invasive Plant Education

We just learned that petunias are considered to exhibit allelopathy, as well as oaks. Allelopathy is the release of chemicals by the plant which discourages competition from other plants. Maybe the oak and petunia would duke it out, but we are rooting for the tree.

Please note that it is difficult to impossible to grow anything under any tree, including grass, because of the needs of the tree roots for moisture and nutrients from the soil and because of the shade from the tree. Here in Texas, we would vote for the trees and spread mulch under the shade of the tree. See our How-To Article Under Cover with Mulch.

 

More Invasive Plants Questions

Pruning drought-stressed butterfly plants from Kerrville TX
August 22, 2011 - Due to the drought, our butterfly bushes have dead branches. Ordinarily we prune the dormant plants in winter, but can we cut back dead branches now?
view the full question and answer

Official list of invasive plants in Texas.
January 25, 2008 - Is there an "official" invasive / noxious weed list for Texas? I have found several lists, but I wanted to know if there was one truly accepted list for Texas. If not, what would be the #1 list yo...
view the full question and answer

Advocacy of non-native plants.
December 10, 2012 - Dear Mr. Smarty Plants, Instead of asking a question, I would like to comment on the seemingly discouraging tone on growing plants or trees out of their native habitat that I have observed from rea...
view the full question and answer

Reseeding a dead lawn in Wimberley TX
February 07, 2012 - Our new house had a sodded lawn that now appears dead. There remains a layer of sandy soil as a part of the sodding process. Is there a way to reseed these existing slabs of sod and what process wo...
view the full question and answer

Elimination of nutgrass
May 06, 2008 - Nutgrass has taken over my vegetable and perennial garden to the point that I can not see my plants or granite sand paths. The two major areas are about 600 square feet in total. What can I do to co...
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