Mexican petunias or Ruellia are easy to grow and can adapt to very dry conditions or swampy conditions but they bloom best in fertile soil with good drainage. These perennialsare  more easily by grown by plants than seed and you can take cuttings from one plant and root them in a mix of half perlite and half peat moss to make lots of new plants. These tropical plants can be invasive in climates like Florida with the warm, moist conditions that they love. They do not survive long in cold climates with wet winters. Keep growing, Marianne Binetti