En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Will non-native and invasive Mexican petunias grow under oak trees from St. Augustine FL

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 Herbs/Forbs Questions

Salt tolerant plants for Long Beach
May 12, 2013 - When Hurricane Sandy hit Long Beach, it has killed all my plants and now almost all of Long Beach is left with dead dried brown vegetation. I want to replant front with bushes and flowers. What woul...
view the full question and answer

Plants for a pool fence in Ohio
October 28, 2010 - I live in Ohio and have a pool with a white vinyl fence. Each year I plant sunflowers around it, but they are so messy when the birds/bees find them. Previously I planted castor beans, however, they...
view the full question and answer

Native plants for a garden in Greenville SC
July 12, 2009 - Beebalm, Threadleaf Coreopsis, a Yaupon Holly, a Southern Magnolia, and a Highbush Blueberry. And as a ground cover in some areas, we have Cinquefoil (which helped me choke out Indian strawberry!) But...
view the full question and answer

Need to stabilize a south facing slope in Henderson, NC
April 30, 2010 - Hi, I have a south facing slope that is heavy clay with rock under it. It gets a lot of sun. I have planted a few bushes and some ground cover, but with all the snow and rain we had this past winter, ...
view the full question and answer

Native plants for Texarkana, TX
March 31, 2011 - I've been searching for a dependable list of attractive north east native plants, for gardens, landscaping, etc. Specifically, native flowers and shrubs.
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