Liatris (Blazing Star) Plant Profile

Liatris pycnostachya / Blazing star
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Liatris flowers may not offer the gardener any fragrance, but they will satisfy three of your other senses: the purple and lavender blooms provide a visual exclamation point in the garden; your ears will be buzzing with the sound of happy bees, and your fingers won’t be able to resist rifling through the fuzzy late summer blooms. Move over fussy roses and diva dahlias, because liatris thrives on neglect.

The genus Liatris belongs to the giant plant family Asteraceae, also known as Compositae. What this means to gardeners is that a liatris blossom is a cluster of many little flowers that appear to be one flower. Pollinators love this! Also known as blazing star and gayfeather, liatris plants bloom from late summer into fall in full sun gardens. The purple, rose, or white flowers of liatris plants look almost like feather boas held erect on several spikes per plant. The leaves are narrow and inconspicuous.

Botanical Name Liatris spicata
Common Name Blazing star, liatris, dense blazing star, gay feather
Plant Type Herbaceous perennial
Mature Size 2 to 4 feet; occasionally to 6 feet
Sun Exposure Full sun
Soil Type Medium, well-drained soil
Soil pH 5.5 to 7.5; neutral to slightly acidic
Bloom Time July to August
Flower Color Purple, reddish-purple, white
Hardiness Zones 3 to 8
Native Area Moist meadows and marshes of eastern U.S.

How to Grow Liatris

Although Liatris plant materials are sometimes marketed as bulbs, they are technically corms, and it’s hard to believe that any life can emerge from these woody little nuggets in a bag. However, these structurally swollen dormant stem parts will send up shoots followed by flowers approximately three months after a spring planting. As with all bulbous types of plants, the largest corms will produce the most impressive flowers, and you should look for corms that are at least 3 inches in diameter. Space the corms 12 to 15 inches apart, and plant them 2 to 4 inches deep.

Liatris takes very little care, but you may need to stake up the stems if they are planted in loose soil.

Light

Choose a site with full sun to plant your liatris corms.

Soil

Just about any soil, at any level of fertility, will successfully grow liatris corms, although quick drainage is essential to prevent rot. Liatris plants prefer a slightly acid to neutral soil pH.

Water

After planting, water the corms thoroughly. The corms need no additional irrigation before the plants emerge. One inch of water a week during the hottest months will prevent stunted flowers and leaf scorch. Apply water to the base of the plants, or use drip irrigation, to avoid spreading fungal diseases. These plants need more water in their first year; afterward, they have very good tolerance to drought and dry soil conditions.

Temperature and Humidity

Liatris is quite tolerant of the heat and humidity of summer weather in warm climates, but it may rot if left in wet soils over the winter.

Fertilizer

Liatris is not a heavy feeder, but if the soil fertility is poor you can apply a balanced flower fertilizer once a year, in the spring as active growth begins.

Propagating Liatris

It’s fun to get new plants for nothing by propagating them, and this is easy to do with liatris corms. Dig the plants up late in the fall after the first freeze has killed the stems, and you will notice tiny corms, called cormels, clinging to the “mother corm.” Pick off the cormels, gently wipe away the soil, and store them in a cool shed or garage until spring planting time.

Varieties of Liatris

Out of approximately 40 naturally occurring species of Liatris, the three commonly available species include spicata, aspera, and pycostachya types. Within these species are several desirable named cultivars:

  • Dotted blazing star: purple blooms endure from August until frost
  • Floristan white: three-foot white flowers in July; long blooming time
  • Kobold: a compact, late July bloomer; 18 inches tall with bright rose blooms
  • Rough blazing star: 6-foot flowers may require support
  • September glory: blooms from August to September with 4-foot purple spikes
Liatris spicata / Blazing star
magicflute002 / Getty Images
Macro close up of pink purple kobold flower (Liatris spicata) against blurred background
Liatris Kobold Ralf Liebhold / Getty Images

Landscape Use

As a native North American flower, liatris flowers are at home in wildflower meadow plantings and cottage gardens, where they will delight butterflies. Their hardiness and low maintenance also make them a welcome addition to the rock garden, where they will mingle with dianthus, penstemon, snow-in-summer, or creeping baby's breath.

Liatris flowers are popular as cut flowers, providing textural and vertical interest to casual vase arrangements as well as summer wedding bouquets. Crafters will appreciate adding dried liatris to their wreaths and garlands: Harvest the flowers at the peak of blooming, strip away the stems and leaves, and hang the flowers upside down in a dry room.

Flower Garden
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Growing From Seeds

For gardeners seeking to plant a large meadow or estate-sized garden, growing liatris from seed is a viable way to save money on a sizable planting. Liatris seeds take about a month to germinate, and the cold moist weather of early spring encourages germination. Rather than trying to fuss over seeds starting indoors, sow the seeds outdoors in the late fall. Mother Nature will take care of the temperature and moisture conditions. Plants grown from seed will not bloom until the second year, but you can plant a small border of sun-loving annuals, such as cleome, to disguise your liatris nursery until it comes to fruition.

Common Pests and Diseases

Liatris is nearly immune to all insects, but it can be prone to several diseases, including leaf spots, rusts, stem rot, powdery mildew, and wilt. To prevent disease issues, space the plants so that there is good air circulation and sunlight exposure.