By Ryan Pankau
Nothing beats the light and airy look of tall, distinctive, grasses in a landscape arrangement. The fluffy seedheads and slender, attractive, stems practically dance in the wind on breezy days, and add texture as well as a structural element to any landscape bed.
For many years, there was a trend toward non-native grasses, according to University of Illinois Extension horticulturists.
“However, there is a growing interest in native prairie grasses, given their inherent adaptability to our climate and their ecological value,” Pankau said.
Big Bluestem, Andropogon gerardii, is one of his favorites for its wonderful height, sometimes reaching up to eight feet, including the seedheads. It’s known for attractive, blue-green foliage, and steams that fade to reddish-bronze in Fall. Interesting seed heads develop late in the growing season and persist into Winter.
Big bluestem fits well in the rear of a border planting, or as a backdrop for other, shorter natives. It works nicely in mass plantings, or as a visual screen when planted in groups. It can be maintained as somewhat of a specimen when mixed into native plantings, although it does tend to slowly spread by rhizomes over time. Spread can be limited by other competing prairie plants, or by periodic removal of spreading shoots.
Switchgrass, Panicum virgatum, is another very tall native grass used for both its ornamental appeal and its tough adaptability to a wide range of soil conditions. However, one issue with switchgrass is its innate ability to spread, either from rhizomes or by seed. For this reason, it’s probably better used in mass plantings, or as a solid border to create visual screening. It works well in problem areas such as wet spots, areas with erosion or locations with some partial shade.
“While switchgrass can have a really nice Fall color, I think its seedheads provide the most interest,” Pankau said. As seedheads mature and expand late in the growing season, they created a cloud-like effect with their open and airy form.
Little bluestem, Schizachyrium scoparium, packs a ton of beauty into shorter stems and fluffier seedheads. Foliage and stems emerge with a deep blue-green color that matures to lighter green with reddish accents at stem nodes. In late summer, flowers begin to emerge as beautiful purplish-red structures that mature into fluffy tufts. Perhaps the plant’s greatest beauty lies in its wonderful Fall color creating a spectacular reddish-purple color. Little bluestem works well as a more vertical component that is not overly tall at only two feet to four feet by the season’s end. It works well in a great variety of garden uses, from mass plantings to small pollinator pockets.
“In my opinion, it is one of the most beautiful and colorful of our native grasses, and it behaves well because it is slow to spread retaining a clump-like habit,” Pankau said.
Another smaller native grass that works well in the landscape is prairie dropseed, Sporobolus heterolepis. Although it does have interesting seed heads and nice fall color, this plant has most value in its fine-textured foliage during the growing season and much smaller size at approximately two feet in height.
Pankau said it is one of his favorite plants to add along a sidewalk or at the front edge of a native garden. It creates a welcoming and inviting view with its fine-textured, hair-like, foliage that wonderfully frames the planting.
“It’s a highly underused landscape plant that deserves more attention given its overall low maintenance requirements and well-behaved habit,” he said.
For more information about plant selection, connect with your local Illinois Extension county office at go.illinois.edu/ExtensionOffice.
Ryan Pankau is a horticulture educator, University of Illinois Extension.
—University of Illinois Extension