Lexington, KY – Kentucky Bluegrass (Poa pratensis) derives its name from its blue flower heads, which appear when the plant is allowed to grow to its natural height of 2 to 3 feet. This grass has spread across half of the United States and into Canada, and is well known as a pasture grass for horses, cattle and sheep. It has been adapted for lawns, sports fields and parks. It withstands a variety of climates, with one big weakness: drought conditions; it has shallow roots so it goes through water quickly.
News Flash: Kentucky Bluegrass isn’t from Kentucky. It’s a European import. Legend has it that Native Americans called it “white man’s tracks” because most everywhere the white man went, they found Bluegrass growing behind him.
When the settlers arrived in Kentucky, they found a prairie with deep-rooted native grasses and wildflowers that held the soil in place and supported a large and diverse wildlife population. These grasses grew in clumps, so they provided nutrition and cover while leaving enough bare ground to allow gamebird chicks to move freely in search of food. Settlers plowed the soil and replaced these plants with corn, wheat, barley and tobacco. They planted Bluegrass brought from home on which their horses and cattle could graze.
This aggressive grass often crowded out native plants. What happened? With the natural ecosystem dismantled, the soils washed away, the land gullied, the waterways were damaged and wildlife populations dwindled. Now we are seeing a resurgence of interest in our native grasses, for grazing, prairie restoration and landscaping.
These very ornamental grasses add structure and movement to the garden, and look wonderful with the native perennials with which they were originally associated. Here is a brief overview of some of our prairie grasses:
Big Bluestem (Andropogon gerardii) has three-pronged, greenish purple flower heads that resemble a turkey foot, on six-foot stems that rise above dense clumps of arching blue-green leaves. It blooms in mid-summer and will grow on most any site, from wet (if well-drained) to dry.
Little Bluestem’s (Schizachyrium scoparium) feathery white plumes appear in late summer/early fall. Its ribbon-like leaves turn russet in the fall, remaining colorful in the winter landscape.
Bottlebrush Grass (Elymus hystrix), a striking grass with seedheads resembling a bottle brush, will thrive in moderate shade in moist to slightly dry conditions.
Indian Grass (Sorghastrum nutans) has long, flat, narrow leaf blades that become yellowish bronze in the fall. Dense bronze-yellow flowers appear in August and September. It grows best in full sun and is fairly tolerant of drought conditions. At 5 to 8 inches tall, it is best used in the back of a perennial bed.
Prairie Switchgrass (Panicum virgatum), also known as tall panic grass, has green leaves with a reddish tint. Panicles of small reddish flowers are borne on the ends of long stems from June to August. In the fall, switchgrass blades turn yellow and the seeds on the panicles turn beige. Switchgrass grows best in full sun and in wet or moist soils. Many switchgrass cultivars of varying heights and characteristics are available.
Sideoats Grama’s (Bouteloua curtipendula) small colorful flower spikes dangle alongside slender stems; its ribbon-like leaves turn golden in autumn. It is highly drought tolerant.