Native Plants
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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.
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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.
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Percentage of plants native to U.S.
June 22, 2007 - About 50% of the plant species in Hawaii are naturalized, invasive, aliens (from other places). What are equivalent statistics for the lower 48 states (continental US) as a whole?
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May 21, 2012 - I am wondering if I plant a Purple Hyacinth Bean vine seed under a tree and allow it to grow up the tree trunk, will it kill the tree?
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October 19, 2012 - Is there an effective herbicide that can be painted on the stumps of Nandina and Wax-leaf ligustrum to keep them from growing back?
Thanks so much!
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Plants for under pine trees in Colorado Springs CO
April 23, 2011 - What can I plant under pine trees in Colorado that will grow every year? Would like ground cover; tried bishop weed.
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