Host an Event Volunteer Join Tickets

Support the plant database you love!

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
1 rating

Tuesday - July 21, 2009

From: Fort Worth, TX
Region: Southwest
Topic: Invasive Plants, Problem Plants
Title: How do you get rid of Mexican Petunia?
Answered by: Jimmy Mills

QUESTION:

How do you get rid of Mexican Petunia?

ANSWER:

Mr. Smarty Plants recently answered a question about the eradication of Ruellia, so I am going to excerpt part of the answer here for you.

The Mexican Petunia (Ruellia brittonia {syn. R. Tweediana}) is a native of Mexico. It can be invasive and is listed as a Category 1 invasive species by the Florida Exotic Pest Plant Council. Its invasiveness is enhanced by its fast growth, prolific production of seeds, and an extensive root system.

Regarding getting it out of your garden, you want to limit the use of herbicide in your garden, so one approach is to pull it out, and keep cutting back new sprouts; not necessarily an easy task. You also want to prevent reseeding by removing flowers after they fade so the seed pods won't develop, and also remove new seedlings as they appear. A chemical control method is to use glyphosphate.  Use this very carefully since it can also eliminate all of your other plants. Cut the Petunias down to the ground and apply the glyphosphate to the stumps of the stems. Be sure to follow the directions and warnings on the label.

For more help closer to home, I suggest that you contact the folks at the Tarrant County office of Texas AgriLife Extension.

 

 

 

 

More Problem Plants Questions

Elimination of nutgrass from native flower bed
October 14, 2007 - Nutgrass!*#!* My new bed in NE Austin wraps around a hot sunny SW street corner. Grass wouldn't grow there [I wouldn't water it.] I removed the turf [mostly stickers] to a depth of about 4", carefu...
view the full question and answer

Want to identify thorny vines growing in Charlotte Hall, MD
April 25, 2013 - I have vines with thorns growing in my wood, vining around the trees and killing them. It grows and vines go up trees of any height all the way to the top. It has green pointy leaves. If it doesn't...
view the full question and answer

How Can I Tell an Invasive Thistle from a Native
May 01, 2012 - Mr Smarty Plants, I have some thistles coming up in my yard. I'd like to keep them if they are native, but not if they are invasive or non-native. How can I tell? My yard is a wild area in West Lak...
view the full question and answer

Getting rid of bermudagrass
July 13, 2010 - How do I get rid of bermuda grass in my San Augustine grass?
view the full question and answer

Killing regrowing shoots of a downed hackberry tree
June 28, 2013 - Hackberry plants won't die. You and others have suggested to cut the suckers or saplings to get rid of them. Over the years I have continued to cut the same saplings and the only thing I have now ar...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.