Big Bluestem (Gerardii)

The Big Bluestem (Gerardii) is generally described as a perennial graminoid. This is native to the U.S. (United States) has its most active growth period in the summer . The greatest bloom is usually observed in the summer, with fruit and seed production starting in the summer and continuing until fall. Leaves are not retained year to year. The Big Bluestem (Gerardii) has a long life span relative to most other plant species and a moderate growth rate. At maturity, the typical Big Bluestem (Gerardii) will reach up to 6 feet high, with a maximum height at 20 years of 0 inches.

The Big Bluestem (Gerardii) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by 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 -46°F. has high tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Conservation: Big bluestem is the dominant grass species of the Midwestern tallgrass prairie. It is mixed with other native prairie species for prairie restoration and highway revegetation. While it does best in moist soils, it can be used for mine reclamation, logging road restoration and other restoration areas that have sandy or droughty conditions.

Erosion control: Big bluestem is planted to stabilize soil. Rhizomes are typically 1 to 2 inches below the soil surface, while the main roots can extend downward to 10 feet.

Big bluestem is also planted to provide aboveground protection against wind erosion. It is used for road cuts, pipelines, detention basin slopes, and areas that need temporary cover during the restoration process.

Ethnobotanic: Chippewa Indians used the root of big bluestem as a diuretic and to alleviate stomach pains. Extracts of the leaf blades were used as a wash for fevers or as an analgesic. The plants were also used to fasten the support poles of dwellings. Moist grass was laid on hot stones to prevent steam from escaping during cooking. It was also used to cover fruit during ripening and under fruit while drying.

Forage: Big bluestem is a high quality forage species for all classes of livestock. Crude protein content of 16-18% is maintained from May through August but drops below 6% in September and October. It is often cultivated as a pasture grass and for hay-making.

Landscaping: Big bluestem is used in wildflower meadows and prairie plantings. It is also effective as a rear border or accent in native plant gardens.

Wildlife: Big bluestem provides shelter for nesting birds and insects. Songbirds and prairie chickens consume the seeds while white-tailed deer and bison graze vegetative parts.

General Characteristics

General: Grass Family (Poaceae). Big bluestem is a perennial warm-season grass. It can be distinguished from other warm-season grasses by blue coloration at the base of the culm and purplish, 3-parted flower clusters that resemble a turkey’s foot. The culms are erect, up to 3 m tall, stout, and are usually covered with a blue-tinted waxy layer. Leaf blades are flat, 15-60 cm long, 0.5-1 cm wide, smooth below and rough above. The inflorescence is typically composed of three spike-like racemes, but can have as many as seven. The racemes bear paired spikelets that are about 1 cm long. Flowering takes place July through October. The foliage changes color seasonally, and culms stay erect through the winter.

Required Growing Conditions

Big bluestem is native to the United States. It occurs in southern Canada, from Maine to Montana, south to Florida and New Mexico and into Mexico. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site (

Habitat: Big bluestem is found in open woods, prairies, meadows, along riverbanks, and roadsides. It is especially abundant in lowland prairies, overflow sites, and sandy areas.

Adaptation The USDA hardiness zones for big bluestem are 4 to 9. It is best adapted to moist, sandy or clay loams but also occurs in dry or shallow soils. It does well in full sun or partial shade. Prairie conditions, like low nutrient and moisture content, have conditioned big bluestem for use in well-drained soil with low fertility. It is not tolerant of heavy clays, extremely wet bottomlands, deep sands, high salinity, or high lime.

Big bluestem is generally shorter in the northern portion of its range, and taller in the southern portion of its range. It is a rhizomatous, sod-forming grass in the tallgrass prairie and has a bunchgrass appearance in more arid regions.

Cultivation and Care

Collect big bluestem seeds when the seed head no longer has a creamy center, usually in September and October. Dry seeds in paper bags for 2 to 4 weeks. Seeds can be stored up to 7 months at 50oF and 50% humidity. Cold stratification (40oF, 35% humidity) may improve germination uniformity. Fill germination trays or pots with moist soil, compacted at bottom. Sow seeds by hand, covering with a thin layer of soil. Keep soil evenly moist during germination and do not use fertilizer.

Greenhouse establishment will occur at alternating day/night temperatures (set at 75/65oF) and 12-14 daylight hours (may be extended artificially). Transplant seedlings into plug cells. Soil does not need to be consistently moist at this stage. In early to late spring, move plugs to cold frame. Seedlings are ready for outplanting when the plant and soil can be completely pulled from the pot as one unit. Outplanting can take place from late May to early October.

Seeds can be sown directly outside from late winter to early spring. Emergence will occur in 4 weeks with several irrigations. Plants will be ready for harvest in mid-summer to late fall.

First-season growth is often slow. Rhizomatic regeneration in following years increases the growth rate.

General Upkeep and Control

Underground rhizomes resprout following fire disturbance. Regeneration is slow if fire occurs during the summer (active growth stage). Regeneration following springtime fire is much more vigorous because the rhizomes have winter-stores of carbohydrates.

Big bluestem can withstand substantial grazing. However if it is continually grazed closer than 6 to 8 inches it will be out competed by other grass species. It is highly palatable to livestock during spring and summer and becomes coarse and less palatable during the fall and winter. Hay should be mowed in early to mid-summer to maintain high nutrition quality.

Plant Basics
Growth Rate Moderate
General Type Graminoid
Growth Period Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Summer
Displays Fall Colors No
Shape/Growth Form Bunch
Drought Tolerance High
Shade Tolerance Intolerant
Height When Mature 6
Vegetative Spread Slow
Flower Color Yellow
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Seed
Moisture Requirements Low
Cold Stratification Required No
Minimum Temperature -46
Soil Depth for Roots 20
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Regrowth Rate Moderate
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 6–7.5 pH
Precipitation Range 12–12 inches/yr
Planting Density 0–0 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 20
Minimum Frost-Free Days 155 day(s)
Salinity Tolerance Medium
CaCO3 Tolerance High
Sustainability & Use
Leaf Retention No
Palatability Medium
Fire Resistant No
Causes Livestock Bloating Low

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