Start Gentian seeds for this lovely perennial herb. Known as Stemless Gentian, Trumpet Gentian or Blauer Enzian, this herb plant typically is found growing in acidic soils. The second botanical name is Gentiana kochiana. The Stemless Gentian herb height is only 4 inches tall and it spreads 6 inches or more. The leaves are evergreen, grow from a basal rosette, and form clumps. The blue flowers are trumpet-shaped and have olive-green spotted throats. The Trumpet Gentian herb likes full sun, is fully hardy, and flowers in late spring and summer.