PL. —Andropogon gerardiiBotanical illustration — drop image
Andropogon gerardii

Big Bluestem

SpringSummerFall
3a9bHardiness zone
Background

Big bluestem is a warm-season perennial grass native to the tallgrass prairie of central and eastern North America, where it was historically the dominant grass of the Great Plains. Its three-branched seed head resembles a turkey's foot — the origin of the common name turkeyfoot. Mature clumps reach 4–8 feet and turn copper to bronze-orange in fall, holding structural interest well into winter.

As a warm-season grass, big bluestem stays dormant until soil warms in late spring, then grows rapidly through summer. Its root system can extend more than 10 feet deep, giving established plants strong drought tolerance. It spreads slowly by short rhizomes and reseeds in open sites. Rich or heavily amended soil produces floppy stems; low to medium fertility is preferred. Cut stems to 4–6 inches in late winter before new growth begins. Mulching is unnecessary and can promote crown rot. Soil pH between 6.0 and 7.5 suits it, and it tolerates clay and sandy loam equally well.

Big bluestem is a keystone species for grassland wildlife. It provides nesting cover and winter seed for multiple grassland bird species and serves as a larval host for several skipper butterflies. Its deep roots sequester significant carbon and resist erosion, making it a functional anchor for prairie restorations, dry meadow plantings, and low-maintenance slope stabilization.

Care guide
SunFull sun
WaterLow
SoilWell-drained, adaptable
Spacing24–36 in
Height4–8 ft
Zone3a – 9b
Native RegionAL, AZ, AR, CO, CT, DE, DC, FL, GA, IL, IN, IA, KS, KY, LA, ME, MD, MA, MI, MN, MS, MO, MT, NE, NH, NJ, NM, NY, NC, ND, OH, OK, PA, RI, SC, SD, TN, TX, UT, VT, VA, WV, WI, WY
Direct sowFrost hardy
Seasonal tasks
winter
cutCut previous season's stems to 4–6 inches before new growth begins. Leaving stems longer delays emergence and can smother new shoots at the crown.
spring
cutDivide crowded clumps using a sharpshooter spade to split the root mass. Replant divisions immediately at original depth and water in. Division revives vigor in clumps older than five to six years.
sowDirect sow seed on the soil surface and press lightly to ensure contact. Germination requires soil temperatures above 60°F. Expect minimal top growth in year one; plants establish their root systems first and fill out in year two.
summer
watchCheck lower sheaths and culms for reddish-brown lesions — an early sign of anthracnose. Thin dense plantings to improve airflow and remove infected material. Avoid overhead irrigation during warm, wet weather.
watchInspect blades for orange or reddish-brown pustules indicating leaf rust. Established plants rarely suffer serious setbacks, but dense, humid conditions increase spread. Divide and space plants to reduce infection pressure.
fall
watchLeave seed heads and culms standing through fall and winter. Multiple sparrow and finch species consume the seeds, and the hollow stems provide overwintering habitat for native cavity-nesting bees.
Common problems

Rust

Symptoms

Orange to brown raised pustules on the undersides of leaves, with yellow spotting on the upper surface. Heavy infections cause leaves to yellow and drop.

Treatment

Remove and destroy infected leaves. Avoid overhead watering and improve air circulation. Apply a sulfur or copper-based fungicide if it spreads. Clear plant debris in fall.

Southern Anthracnose

Symptoms

Dark sunken lesions on stems and petioles, often girdling and blackening the crown; plants wilt and collapse in patches during warm, wet weather.

Treatment

Plant resistant varieties, ensure good drainage, and avoid dense overcrowded stands. Remove infected plants and rotate to non-legume cover for a season.

Helminthosporium Leaf Spot

Symptoms

Small oval to elongated tan or brown lesions with reddish-purple borders appear on leaf blades and sheaths. In severe cases, blades yellow and die back from the tip downward.

Treatment

Remove and dispose of heavily infected foliage. Avoid overhead irrigation and improve air circulation by thinning dense plantings. Fungicide applications are rarely warranted on established native grasses; correcting site conditions — spacing, drainage, and fertility — is the primary control.