Prairie Gentian Eustoma grandiflorum

Eustoma grandiflorum, or Lisianthus, is a flowering biennial in the gentian family, native to the mid-western United States that will survive the winter temperatures of USDA Zones 8-10. It is often considered an herbaceous perennial, but it is more typically grown as an annual. Flowers grow on single or branching stems and bloom from summer to first frost. Flowers are very showy in pink, white, and lavender and make good cut flowers.

It does best in average, moist, well-drained soil with full morning sun and afternoon shade. The plant is noted for good drought tolerance.

Because the seeds are very small and it can take months for a plant to mature from seed, it is more often purchased and transplanted. If you wish to grow from seed, start the seeds indoors 10 to 12 weeks before last frost. It can take about 5 months from planting to first bloom. You can pinch back the plant to encourage branching.

Cultivars typically grow 18 to 30 inches tall, although some dwarf varieties only reach 6 to 8 inches tall. The dwarf plants are effective in pots or as houseplants. Cultivars also offer a range of flower colors including shades of pink, blue-violet and white. Some double-flowered varieties are also available. Lisianthus is an excellent cut flower.

Diseases, Insects, and Other Plant Problems:

No serious insect or disease problems. Look out for viruses and stem cankers. It is susceptible to a number of fungal diseases.