What do we plant for fall color? Most of us would quickly list off maples and crabapples, or perhaps a burning bush (aka winged euonymus). But what about grasses? Some ornamental grasses have impressive fall foliage, and it lasts all winter.
Ornamental grasses are everywhere. What was once a fairly obscure group of landscape plants have emerged into the spotlight, and their popularity shows no sign of fading. That’s not surprising, considering how much they have going for them—flowing leaves, towering seed heads, a fountain shape unlike that of shrubs or perennials that adds contrast and texture to the garden.
For cold-climate gardeners, one major asset is grasses’ ability to look attractive almost all it down in late winter to make way for new spring growth.
Most ornamental grasses turn a lovely tawny gold in fall, and then keep that hue all winter. But some take on more vibrant colors. One of the best for Colorado gardens is Little Bluestem, Schizachyrium scoparium, pictured above.
This North American native is a major component of the tallgrass prairies, where it thrives in full sun. Little Bluestem is adapted to a wide range of conditions: it’s hardy from zones 3 to 9 and tolerates heat, humidity, drought, deer, crummy soil, smog, and even the allopathic chemicals produced by Black Walnuts. That’s one determined plant! Moreover, it’s not bothered by insects or diseases.
I’m glad this grass is easy to grow, because I definitely want it in my garden. During the growing season, the plants are a soft blue-green, forming the perfect background for the yellow, orange, and purple flowers I grow. Some cultivars are bluer than others. ‘The Blues’ is aptly named, ‘Blue Heaven’ is a bit lighter, and ‘Prairie Munchkin,’ a compact variety, starts out with celery-green leaves before they turn a lovely silver-blue as they mature. Burgundy flowers with silvery seedheads appear in August and may persist into winter.
As if that isn’t impressive enough, come fall, you won’t believe the brilliance. My favorite cultivar, ‘Blaze’, turns a bright coppery-orange, streaked with fiery reds, purples, and pink. Wow! It really looks as if it’s ablaze. Other cultivars feature combinations that include these hues, as well as mahogany, maroon, purples, and shades of blue. As the season progresses, the colors settle down a bit, but as you can see from the photo, the plant stays a lovely copper all winter.
Little Bluestem isn’t the only grass that provides color this time of year. Flame Grass (Miscanthus sinensis ‘Purpurascens’, aka M. purpurascens) has two seasons of glory. The flowers start out a bright magenta, set off by gray-green foliage. In fall, the seed heads turn white, just in time to be complemented by the now flaming orange-red leaves.
Japanese Blood Grass (Imperata cylindrica ‘Red Baron’), shown here, also makes a beautiful statement in the fall garden. Hardy in zones 5 to 9, it tends to be invasive in warmer climates where it is often designated a noxious weed. Here in Colorado it behaves itself, so we can enjoy it without fear of world domination. Cogongrass, as it’s also known, tolerates a wide range of soils and exposures. All we have to do is add water. You might guess from the name that the leaves turn red. Indeed they do, every shade of red that you can imagine.
Then there are the fountain grasses, in the genus Pennisetum. While many are frost tender, some manage just fine in cold winter areas. ‘Burgundy Giant’ and ‘Rubrum are two cultivars with season-long red foliage. Both are hardy down to zone 4. ‘Burgundy Bunny’ (P. alopecuroides), hardy in zones 5 through 9, is a dwarf fountain grass with white flowers set off by red and gold fall color persisting well into winter.
I don’t have room here to describe every ornamental grass with great fall color. Some other recommended grasses (hardy to at least zone 5) include Feather Reed Grass (Calamagrostis x acutiflora), Frost Grass (Spodiopogon sibericus), Japanese Forest Grass (Hakonechloa macra ‘Aureola’), Prairie Dropseed (Sporobolus heterolepis), Red Switch Grass (Panicum virgatum ‘Shenandoah’), and Tall Moor Grass (Molinia caerulea arundinacea).
With all these choices, every garden should feature the bright fall hues of ornamental grasses.