Prairie dropseed is among most beautiful native grasses
Ornamental grasses are reaching their peak in late summer landscapes. Planted among perennials in borders, they contribute contrasting texture, form and movement to the design. And just as the blooms of many summer-flowering perennials begin to fade, grasses step up to take center stage.
One of the best ornamental grasses to combine with perennials is prairie dropseed, botanically named Sporobolus heterolepis.
Native to our area and hardy in USDA zones 3 to 9, prairie dropseed is now often found growing in prairies and along railroad tracks. In cultivated gardens, it prefers a spot in full sun with dry, gravelly soil, but is adaptable to a wide range of soils including those with heavy clay. Once established, prairie dropseed is tolerant of short periods of drought.
This fine-textured grass grows 18 inches tall (up to 3 feet in bloom) and 2 to 3 feet wide, forming an elegant fountain of very narrow, medium green foliage. In August, 2- to 3-foot slender spikes rise from the foliage displaying airy, pink-blushed light brown flowers with a unique fragrance. Some say they smell like coriander. I think they smell just like buttered popcorn, and not the kind popped in a microwave, but the real deal found at the movie theater.
The foliage turns a delicious pumpkin-rust color in fall and fades to light bronze in winter. Sporobolus heterolepis is never bothered by pests or disease. It is, like other native grasses, the larval food source of several butterflies. The Plains Indians collected and ground the seed to make flour. The sparrows feast on the seeds in my garden.
Prairie dropseed rarely self-seeds, but seed can be gathered and planted to start new plants, if one has resolve and patience. Seeds are not only difficult to germinate, slow-growing prairie dropseed may take up to five years to become a full-size plant. Impatient gardeners can propagate this grass by dividing mature plants.
The only care required by prairie dropseed is cutting back the dead foliage in spring, weeding the area where it grows to eliminate competition for water and nutrients and watering during extended periods of drought.
Plant prairie dropseed in perennial borders where its fine texture and arching form combines with coarse-foliaged, upright perennials like coneflowers, black-eyed Susan and butterfly weed. It is also lovely planted with small shrubs in foundation plantings and as an easy-to-care-for ground cover. And, of course, it is perfect for prairie or meadow gardens.
Sporobolus heterolepis 'Tara' is a dwarf cultivar. It grows more upright (and less like a fountain) than its parent. Growing just a foot tall and wide, it is perfect for the front of a perennial border or to edge a sunny path. Flowers reach 24 inches tall and its fall color is even more spectacular than the species.
Many believe prairie dropseed is one of the most beautiful native ornamental grasses. I wholeheartedly agree, and whenever I walk through my yard and get a whiff of buttered popcorn, I pat myself on the back for planting it (and then I head to the movie theater).
• Diana Stoll is a horticulturist, garden writer and speaker. She blogs at gardenwithdiana.com.