Native Ornamental Grasses
Prairie dropseed, Sporobolus heterolepis
Ornamental grasses first began to gain popularity in Germany in the 1930s courtesy of nurseryman Karl Foerster. He spent years collecting samples and seeds from all across the world, including the Americas, to study them before introducing them to the landscape world. Today there are so many varieties available that there is one for every landscape. Those that are native are an exceptionally ecologically sound choice.
As with any type of plant, selection of ornamental grasses must be done according to the old adage “right plant, right place.” Choose one that fits the space, light, and environmental conditions for the landscape. Once in place, the grasses require minimal maintenance, are relatively disease and pest resistance, and are drought resistant.
The primary maintenance required for ornamental grasses will be an annual pruning and a division of large clumps. Allow the grass to stand through the winter. This provides winter interest to the landscape, provides shelter for pollinator reproduction, and protects the roots. In the spring, before new growth is initiated, cut it back to a few inches from the ground.
Divide the plants around every 3-4 years or when the center of the plant begins to die out. This can be accomplished in the early spring before new growth occurs, but will take some muscle to accomplish. Dig out the entire clump, cut into sections with a sharp knife, plant one of the sections in the original location, and either give away the remainder or plant in a new location.
One of the most common native ornamental grasses is Little Bluestem (Schizachyruim scoparius). A major element of the Wisconsin prairie, it requires full sun and well-drained soil; adding some organic matter to heavy clay soils will aid this beauty. Little Bluestem is suited for even a small city lot. It will grow to 24-36 inches tall and spread 12-18 inches. The blue-green foliage turns to a coppery color later in the season with fluffy seed stalks that mature in late fall.
A larger lot can accommodate Big Bluestem (Andropogon gerardii). This workhouse of the prairie is very similar to Little Blue Stem but much grander. It should be used as a focal point rather than a border plant due to its 4-7 foot height and 2-3 foot spread. It has similar coloring and growing conditions as its cousin. Both of these plants have extensive root systems (Big Blue more so because of its size) and can be used as erosion control in challenging locations.
Switchgrass (Panicum virgatum) is another large-sized native grass. At 3-8 feet tall and 3 feet wide, it is not for the faint of heart. It makes a stunning backdrop for a flower garden or part of a native garden with its brilliant golden fall color.
Prairie Dropseed grass (Sporobolus heterolepis) is a tidy, smaller clump forming grass, only 24 inches tall and 18 inches wide. It has a buttery popcorn fragrance that makes it especially appealing. The emerald green foliage turns a golden color in the fall. Typical of the native grasses, this is a tough plant that will tolerate difficult situations. It is a good border plant, but position it back far enough that it does not drape over any pathway.
This barely skims the native grasses available, but space prevents further discussion. Questions about other choices can be sent to https://hort.extension.wisc.edu/ask-a-gardening-question/
Carol Shirk
Certified Master Gardener