Eustoma is a very small plant genus, made of three different species, all of which belong to the Gentian plant family, Gentianaceae.
These plants hail from South America, the Caribbean, Mexico, and southern states of the US.
Classified as tender perennials, these plants can be treated as bedding plants in colder parts of the world, where they will still add a lot to any planting scheme.

You may see them labeled as Lisianthus, Prairie Gentian, or Eustoma, and they are available in single petal form or double-petal flowers, in shades of blue, white, ivory, purple, and pink (see also What You Should Know About Gentian).
You may notice that the single flowering varieties look similar to tulips and poppies, and the double flowering types can resemble peonies, and can even be confused with roses.
Eustoma Name Origin
The genus name is Greek, with a combination of the prefix eu and stoma, which translates as pleasing mouth, referring to the shape of the flowers.
Lisianthus is also Greek, made from lissos and anthos, meaning smooth flower.
Eustoma Flower Symbolism
Prairie Gentians symbolize optimism, happiness, and hope.
To some people, these flowers represent a long life, tranquility, gratitude, love, and affection.
Eustoma Growing Requirements
Eustoma plants are hardy in USDA zones 8 through to 11, though you may be able to grow them as summer bedding plants in colder climates.
They bloom all the way through summer, and if the weather is kind, well into fall as well.
Eustoma plants can reach between 15cm and 3 feet tall, depending on the type you go for.
They will do well in a sunny position or partial shade, as long as you give them well-draining, consistently damp soil which has some nutrients.
They require an average amount of water, but they do require some attention from you occasionally, to help keep them at their best.