Q: I bought a pink Mexican petunia and it has taken over my yard. I am finding it every where. What can I do to get rid of it?
A: Truly this plant is a pest in our area. Mexican petunia, Ruellia brittoniana, is listed as a Category I invasive species by the Florida Exotic Pest Plant Council. This means that it is “altering native plant communities by displacing native species, changing community structures or ecological functions, or hybridizing with natives”. This warning applies to all parts of the state of Florida (and other areas with similar mild climates). Where hardy, the Mexican petunia excels at invading wetlands. Your first strategy should be immediate application of glyphosate (Round-up) directly onto each plant. You must use great care because this product will kill anything green and growing so you should paint each plant rather than spray it. Painting the plants will be a tedious job but very effective. Mexican petunia is similar to Boston fern in its ability to reproduce rapidly and effectively in most soil and light conditions.