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 Trees Questions

Newly planted nuttall oaks from Houston TX
November 16, 2012 - I recently purchased two Nuttall Oak Trees in Houston Texas (October). They are both 15' or taller. I planted them within 24 hours of being delivered, watered them in, staked them, and within 3-4 d...
view the full question and answer

Propagating Magnolia grandiflora from Murfreesboro TN
August 03, 2011 - There are several Magnolia grandiflora (Southern magnolia) that have been planted in my neighborhood in middle Tennessee by a landscaping company, and now that they all appear to be producing seeds, ...
view the full question and answer

Failure to bud out of Shumard oaks in Floresville TX
April 16, 2010 - Question: I have a Shumard red oak (9-10ft tall) that I planted last October as its leaves were turning a brilliant red color. However, it's the only tree that did not bud this spring. I scraped t...
view the full question and answer

Trees for home in Kansas
April 01, 2012 - I am needing help planting trees in my yard. It's a new construction home and I would like a tree that won't get into the septic system easily. Also, I have to plant 3 other trees as well due to the...
view the full question and answer

Leaves wrinkling on Tecoma stans from San Antonio TX
August 16, 2013 - My two year old esperanza (planted in the ground) froze back last winter, came back from the roots & has been doing well all summer. Recently one branch has leaves that are nice & green but very wrin...
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center