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
Not Yet Rated

Thursday - July 02, 2009

From: Vacaville, CA
Region: California
Topic: Invasive Plants, Problem Plants
Title: How can I eradicate Mexican Petunia from my garden in Vacaville CA?
Answered by: Jimmy Mills

QUESTION:

Can you tell me the best way to eradicate the plant Ruellia, commonly known as Mexican Petunia, from my garden?

ANSWER:

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 don't want to spray 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 University of California Cooperative Extension in Solano County.

 

 

More Problem Plants Questions

Identification of vine with hair-like prickles
January 04, 2013 - Trying to find out what kind of vine I ran into yesterday while climbing a deer stand. While pushing limbs and vines down from around me, I noticed hair-like thorns stuck in my sleeves and hands. This...
view the full question and answer

Bulletproof plants from Burleson TX
April 18, 2013 - I recently wrote you a question concerning planting a privacy plant consisting of wax leaf ligustrum on my country property. Your answer was immediate (thank you-I am impressed). I like the wax leaf ...
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

Controlling sandburs from Austin
February 24, 2013 - Hello, What is the best way to prevent sticker burrs from growing in a rocky bed with no grass. There are many other plants we want to preserve and a drip line to keep them watered. We have 2 small k...
view the full question and answer

Getting rid of Adams needle (Yucca filamentosa)
June 24, 2009 - My friend is changing her flower beds around and is wanting to eliminate an Adam's needle that has been there for several years. She has already dug it up and now is trying to get rid of all the new...
view the full question and answer

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