"Mexican petunia is another example of plant that is being sold over the internet and in garden centers as a flowering plant or “handy perennial edging plant for flower beds and as colorful groundcovers”. The problem is that the Mexican petunia is highly invasive and is listed as a Category 1 invasive species by the Florida Exotic Pest Plant Council. Mexican petunia received this classification because of its invasion and distribution within native plant communities."
http://plants.ifas.ufl.edu/node/380