Gentiana

( jen - tee - AY - nuh )

At-A-Glance Information

Commonly called Gentian, this flowering perennial (sometimes biennial or annual) needs full sun in the coolest climates of its zone range and regular water. The tubular flowers come in various shades of blue. These plants are native to many regions of the world, including Asia, Europe, the Americas, Africa, Australia, and New Zealand. Most plants are difficult to grow outside of their natural habitat, but some cultivars have been bred for garden conditions. Use Gentian in shaded areas of the garden, in mixed beds, or grow them in containers. Take care when planting these flowers in the landscape, as some plant parts are moderately toxic to humans and pets.

Gentiana Species and Varietals

Gentiana is the type genus member of the plant family Gentianaceae, and includes over 300 distinct species. The genus name is a tribute to Gentius, the Illyrian king who allegedly discovered the plants' tonic properties. These flowers grow best in USDA hardiness zones 3-7 or Sunset growing zones 2-6 and 14-17, though this can vary somewhat depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Gentiana acaulis (Stemless Gentian, Trumpet Gentian, Gentianella, Large-Flowered Gentian, Blauer Enzian, Blue Gentian)
This species is native to the mountains in central and southern Europe and forms a mat 3-4 inches tall and 1 foot wide. Foliage is glossy and dark green. In summer, rich blue flowers with interior green spots bloom. Divide every 2-3 years for best performance.

Gentiana alba (Plain Gentian, Pale Gentian, White Gentian, Cream Gentian, Yellow Gentian, White Prairie Gentian)
This species is considered rare in some parts of its native range in North America, and produces yellow to white flowers. These plants form thick taproots. Individual plants reach up to between 1 and 3 feet tall when mature and in bloom.

Gentiana andrewsii (Bottle Gentian, Closed Gentian, Closed Bottle Gentian, Blind Gentian, Cloistered Heart, Prairie Closed Gentian)
This species is native to northeastern North America, and produces a perennial herbaceous plant that blooms in late summertime. Flowers are rich blue, and petals are fused together, forming a closed bottle shape. Foliage is glossy and green. These plants prefer very moist soils, growing naturally in fens and sandy areas near lake shorelines.

Gentiana asclepiadea (Willow Gentian, Willowleaf Gentian)
This native of Europe and western Asia has arching stems topped with deep blue flowers that open in late summer and early fall. The plant forms a clump 2-3 feet tall and 1.5 feet wide, making it one of the larger plants in the genus. These plants love rich, neutral to acidic soil and do great when planted amongst ferns. Needs partial shade for best performance. This species grows well in USDA hardiness zones 3-9.

Gentiana calycosa (Explorer's Gentian, Rainier Pleated Gentian, Mountain Bog Gentian)
This species produces flowers that range in color from deep blue to purple. Plants form hardy, thick green leaves on thin red stems and reach up to 2-18 inches tall when in bloom. Explorer's Gentian is native to the western United States, and prefers to grow in rocky slopes, wet meadows, and bogs. Mountain Bog Gentian does well in USDA hardiness zones 3-8.

Gentiana cruciata (Cross Gentian, Star Gentian, Crosswort Gentian)
This species of Gentian is native to Europe, Turkey and Siberia. It grows to form a rosette of thick leaves up to 8 inches long. Stalks clad with leaves sprout 8-16 inches tall and hold clusters of dark blue flowers towards the tips, nestled amongst the leaves. This species is not fussy about soil, and blooms in summer and early fall.

Gentiana decora (Appalachian Gentian, Showy Gentian)
This species is native to the southern Appalachian mountains, and prefers to grow in oak woodland areas. The species grows well in USDA hardiness zones 5-7. Flowers are bluish white, and bloom in late fall. Individual plants reach up to between 11 and 25 inches tall when mature and in bloom.

Gentiana glauca (Pale Gentian, Glaucous Gentian, Alpine Gentian, Inky Gentian)
This species is native to eastern Asia and northwestern North America and grows well in USDA hardiness zones 3-5. It produces a basal rosette of green leaves from an underground rhizome, and reaches 6 inches tall when mature. Flowers are blue to blue-green. This species prefers moist, treeless habitats and commonly grows in tundra landscapes.

Gentiana lutea (Great Yellow Gentian, Bitter Root, Bitterwort, Gall Weed)
This species is native to the mountain ranges of central and southern Europe. These plants reach between 3 and 6 feet tall when mature, and produce yellow flowers. Great Yellow Gentian grows in grassy alpine environments. These plants were sometimes used in brewing beers before the discovery of hops, due to their bitter-flavored roots. Great Yellow Gentian grows well in USDA hardiness zones 3-8.

Gentiana newberryi (Alpine Gentian, Newberry's Gentian)
This species is native to California and Oregon, and forms a small herbaceous plant that grows along the ground. Leaves are green, sometimes with purple coloration on margins and tips. Flowers are white and trumpet-shaped. This species grows best in USDA hardiness zones 4a-7b.

Gentiana pannonica (Hungarian Gentian, Brown Gentian, Round-Petalled Gentian, Gentiane de Hongrie, Genziana Rossinga, Horec Panónsky)
This perennial plant reaches between 8 and 24 inches tall when mature, and produces a strong, upright stem. Flowers bloom from July through September, and are maroon, brownish, or purplish. This species grows well in USDA hardiness zones 4-8.

Gentiana punctata (Spotted Gentian, Tüpfel-Enzian, Getüpfelter Enzian, Gentiane ponctuée, Genziana punteggiata)
This species is native to central and southeastern Europe. These plants reach between 8 and 24 inches tall when mature, and produce yellow flowers that are heavily marked with maroon to purple spotting.

Gentiana saponaria (Soapwort Gentian, Harvestbells)
This species forms a stout taproot and produces blue to purple flowers. Blooms stay closed, similar to other 'bottle' gentians. Flowers are pollinated by bumblebees. These plants are native to eastern North America, from Wisconsin to New York and south from Texas through Florida and grow well in USDA hardiness zones 4-9.

Gentiana sceptrum (King's Scepter Gentian, King's Gentian, Staff Gentian)
These plants are native to the west coast of North America, from British Colombia down through northern California and grow well in USDA hardiness zones 3-8. They prefer to grow on wet areas in hills and mountains, including flooded meadows and bogs. Stems are leafy, and flowers are large and dark blue to purple.

Gentiana septemfida (Crested Gentian, Summer Gentian, Everyman's Gentian, Crested Summer Gentian)
This species grows best in USDA hardiness zones 3-8 or Sunset growing zones A1-A3, 1-6 and 14-17. They are native to Türkiye, Iran, and Central Asia and have arching, sprawling stems 9-18 inches in length. The plant forms a mass 8 inches tall and 1 foot wide. Flowers are purple-blue and bloom in late summer in clusters. Subspecies Gentiana septemfida lagodechiana (Lagodekhi Crested Gentian) forms a similar plant, but has more widely spaced flowers.

Gentiana setigera (Mendocino Gentian, Elegant Gentian)
This rare species is native to southern Oregon and northern California, where it prefers to grow in serpentine soils. These low-growers run along the ground, producing stems that reach about 16 inches long. Flowers are small and bright blue, with speckled white centers. Great as a delicate small-space groundcover.

Gentiana sino-ornata (Showy Chinese Gentian, Chinese Gentian, Autumn-Flowering Gentian)
Native to China and Tibet, this plant forms a rosette of bright green foliage 7 inches tall and a little wider, which sends out trailing stems that produce blue flower clusters in early autumn. These like acidic soil and partial shade. Mulch these plants with gravel for best performance. Best in USDA hardiness zones 5-8.

Caring for Gentiana

Take care when planting these flowers in the landscape, as some plant parts are moderately toxic to humans and pets. Although these plants are considered to be generally difficult to grow, the species listed above are great for gardens, and if provided the right care and conditions, can be grown successfully. These gorgeous bloomers can be grown from seed or purchased as starts from a reputable nursery. Gentiana plants prefer to be grown in full sun to partial shade. Ideally, this means they should receive between 4 and 8 hours of direct sun each day for the best flowers and overall growth. They prefer to be grown in soil that is rich in organic matter as well as well-draining. They like a soil that has pH of between 5.5 and 7.0. If local soils are compacted, do not drain well, or are particularly poor in nutrients, make sure to amend the planting area with plenty of organic matter or compost before installing. Apply a thick layer of mulch around the base of the plant after planting, ensuring that mulch stays at least a few inches away from the stems. This will increase soil moisture retention, suppress weed growth, and maintain a constant soil temperature.

Water new plantings regularly as they develop strong root systems. At maturity, these flowers like a consistently moist soil. About an inch of water per week is recommended. Each year in springtime, apply a 2-inch layer of organic compost around the planting area to improve soil structure, drainage, and nutrient load. Pruning these plants is relatively straightforward. Deadhead as needed to keep plants looking tidy. After their bloom in springtime, foliage can be lightly trimmed. Gentiana plants can be annuals, biennials or perennials. Annuals are typically pulled at the end of the growing season and composted. Perennial plants will typically last for between 3 and 5 years before needing to be replaced; many will re-seed freely in the landscape, providing new plants indefinitely.

Propagation

Gentiana flowers can be propagated by division or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division method. To propagate your Gentiana flowers, follow the instructions below:

Propagating Gentiana by Seed

To propagate by seed, you will need a container, a pot or tray, potting medium, and a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. Gentiana seeds are held in seed pods which are brown, present atop stems after flowers have faded. Collect seeds from the pods and place them in a container during harvesting to avoid losing them.
Get your container prepared. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them lightly with soil and water with a spray bottle. Place the sown seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2 to 4 weeks from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots. Loosen the seedlings from the potting medium by digging down with the tines of a fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet. Keep your seedling in an area with bright light and temperatures between 65 and 75 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when the seedling can be hardened off and then planted outdoors.

Propagating Gentiana by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil, compost, and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in spring or fall (after the plant has entered dormancy and been cut to the ground, but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance. To propagate by division, follow these steps:

Gather your materials. Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the roots. Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick root section. Remove any dead roots at this time.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home.