Rent Shop Volunteer Join

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

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

Invasive native blackeyed susans from Warren OH
August 07, 2013 - In our demo garden we master gardeners in NE Ohio have been unable to get rid of black-eyed susans which have, like the other person, prevented or "killed" the other perennial plants. They are spre...
view the full question and answer

Eliminating weeds from seeded wildflower stands
June 25, 2007 - We live in Eastern Central Texas in a small community on Texas Highway 7. Last fall, we went to the Wildseed Flower Farm near Fredricksburg and purchased a bag of mixed wildflower seeds and planted...
view the full question and answer

Need help fighting grass burs in La Grange, TX.
January 22, 2013 - I have 4 acres of wildflowers planted in my front yard. Unfortunately, grassburs have crept in & I need to control them with a pre-emergent. Will this keep the wildflowers from blooming? Also, would l...
view the full question and answer

Problem with weeds in the buffalograss
June 11, 2008 - Dear Mr. Smarty Plants, I'm about to throw in the towel! My back 'lawn' of buffalo grass (609) is almost all 'weeds'! Native ruellia and lyre leaf sage have taken over and as the area has gott...
view the full question and answer

Methods of controlling poison ivy
April 19, 2005 - What do you suggest for controlling poison oak (ivy)?
view the full question and answer

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