Ruellia simplex, the Mexican petunia, Mexican bluebell or Britton's wild petunia, is a species of flowering plant in the family Acanthaceae. It is a native of Mexico, the Caribbean, and South America. It has become a widespread invasive plant in Florida, where it was likely introduced as an ornamental before 1933.
Mexican petunia grows and blooms best in full sun or partial shade. It will grow in shade, but doesn't bloom as much and looks leggy and lanky. This sun-loving perennial likes rich, slightly moist soil so mulch the plants to maintain consistent soil conditions, especially during hot, dry weather.
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