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?

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

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
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 Non-Natives Questions

Information about non-native Canaga odorata, ylang-ylang
July 10, 2008 - can you tell me the composition of canaga odarata or ylang-ylang flower? also, beneficial effects? it's for my science project..
view the full question and answer

Non-native citronella mosquito plant wintering inside in Charlotte NC
October 20, 2011 - Can I bring the citronella mosquito plant in the house over the winter, or should it be planted outside. I live in Charlotte, NC.
view the full question and answer

Replacement for Globe Thistle in Virginia
June 15, 2013 - Hi, We are trying to get our garden to be 100% North American Native and are at about 90% native to our region. One of the last plants we have to replace is our Globe Thistle. Do you have a good r...
view the full question and answer

Seeds of agave attenuata from San Diego CA
April 16, 2012 - After the agave attenuata bloom dried up there are seeds like thing hanging on the foxtail; do I leave it until it dies or do I chop that down. Are those seeds for propagation. The leaves of the plan...
view the full question and answer

Removing invasive Dichelostemma firecracker plant from Austin
April 12, 2012 - We have dichelostemma firecracker plant & cannot kill it. We need help in getting rid of this plant. Spent another 3 hours digging up corms this afternoon. It is invading our backyard & want it kil...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center