Prairie Blazing Star (Pycnostachya)

The Prairie Blazing Star (Pycnostachya) is generally described as a perennial forb/herb. This is native to the U.S. (United States) has its most active growth period in the summer . The Prairie Blazing Star (Pycnostachya) has green foliage and inconspicuous purple flowers, with a smattering of conspicuous brown fruits or seeds. The greatest bloom is usually observed in the mid summer, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The Prairie Blazing Star (Pycnostachya) has a moderate life span relative to most other plant species and a moderate growth rate. At maturity, the typical Prairie Blazing Star (Pycnostachya) will reach up to 3.5 feet high, with a maximum height at 20 years of 0 inches.

The Prairie Blazing Star (Pycnostachya) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by corms, cuttings, seed. It has a slow ability to spread through seed production and the seedlings have low vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -33°F. has medium tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Prairie blazing star can be used for prairie restoration and landscaping, roadside plantings, wildlife food and habitat, wildflower gardens (because of its attractive flowers), and as a small component in seeding mixtures.

General Characteristics

Prairie blazing star is a hardy, native perennial herb that grows from a tuber. It is one of the most conspicuous of the prairie inhabitants, as its leafy stems grow erect to a height of 5 feet. The narrow leaves on the lower two-thirds of the plant are so crowded that to the casual observer they may appear spiraled rather than closely alternate. Lower leaves, up to 4 inches long and ½ inch wide, are larger than those further up the stems. Both the leaves and stems usually display short, stiff hairs.

The top two-thirds of prairie blazing star is a spike of rose-purple, thistle-like flowers that are given a somewhat fuzzy appearance by extended white stamens (male flower parts) and pistils (female flower parts). Flowering starts at the top of the spike and moves progressively downward. Each flower head along the spike is made up of 5 to 12 tubular florets. A dense circle of bracts (tiny, modified leaves) surrounds the base of each flower head. The tips of these long, pointed bracts tend to spread and curve back toward their bases. Bracts of this species may have a purplish tinge.

All Liatris produce flowers in wand-like spikes or racemes. Their flowers are produced in late summer and autumn. They multiply by offsets from their cormlike base, or may be grown from seed, which should be sown in autumn. They will grow and produce flowers in poorer soil than most garden plants, but thrive best in good, rich garden soil, and require no special care. The showiest species are Liatris elegans and Liatris pycnostachya. The slender seeds of Liatris are usually less than 1/4 inch long. The seed narrows toward the base and is tipped with a set of soft bristles about as long as the seed itself. There are 10 ribs or ridges running along the length of the seed. Prairie blazing star seeds per pound average 131,000.

Required Growing Conditions

Prairie blazing star is found throughout the tall grass prairie biome, often in thick stands on damp prairies and open bottomlands from Minnesota and Wisconsin south.

Cultivation and Care

Prepare a clean weed free seedbed by disking and harrowing or using chemical weed control. Firm the seedbed by cultipacking. Seedbed should be firm enough to allow seed to be planted ¼ inch deep. For prairie restoration or diverse plantings for wildlife, prairie blazing star can be incorporated into seed mixes at a rate of 4 ounces pure live seed/acre. Use unstratified seed in fall and stratified seed in the spring. A seeder with a legume box works well in the seeding operation, although other types of seeders or drills maybe used. Apply no fertilizer the establishment year unless a soil test indicates a severe deficiency of phosphorus and potassium. Use no nitrogen during the establishment year as this can encourage weed competition.Seedling vigor is good and stands are comparatively easy to establish where competition is controlled.

General Upkeep and Control

During establishment, reduce weed competition by mowing above the height of the prairie blazing star or using approved herbicides. In established stands, prescribed burning may be appropriate where plant vigor declines or where invader species threaten native mix stands.

Pests and Potential Problems Medium to severe lodging has been documented when growing prairie blazing star in a monoculture planting.

Environmental Concerns Prairie blazing star is not considered weedy or an invasive species and has not been noted spreading to adjoining areas. Seedlings have not been noted spreading from original plantings or if they do spread, the rate of spread is not alarming.

Cultivars, Improved, and Selected Materials (and area of origin) Two source identified composites of prairie blazing star from northern and central Iowa were released in 1999 by the Elsberry, Missouri Plant Materials Center. The cultivar ‘Eureka’ (Kansas) was released in 1975 by the Manhattan, Kansas Plant Materials Center.

Plant Basics
Growth Rate Moderate
General Type Forb/herb
Growth Period Summer
Growth Duration Perennial
Lifespan Moderate
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Mid Summer
Displays Fall Colors No
Shape/Growth Form Multiple Stem
Drought Tolerance Medium
Shade Tolerance Intolerant
Height When Mature 3.5
Vegetative Spread None
Flower Color Purple
Flower Conspicuousness Yes
Fruit/Seed Abundance Low
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Corms, Cuttings, Seed
Moisture Requirements Medium
Cold Stratification Required Yes
Minimum Temperature -33
Soil Depth for Roots 14
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Slow
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 6–8.5 pH
Precipitation Range 16–16 inches/yr
Planting Density 2700–7000 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 14
Minimum Frost-Free Days 120 day(s)
Salinity Tolerance Low
CaCO3 Tolerance Low
Sustainability & Use
Leaf Retention No
Palatability Medium
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database,
National Plant Data Center, Baton Rouge, LA 70874-4490 USA