By Mary H. Meyer, Associate Professor, Department of Horticultural Science, University of Minnesota


Just over 10 years ago, Mary H. Meyer, an associate professor with the Department of Horticultural Science at the University of Minnesota, developed a list of recommended grasses for retailers in Minnesota. Since the list was distributed at a presentation at the Minnesota Nursery Landscape Association in 1990, retailers have grown and stocked these 10 plants, proving that people listened to her suggestions.

     Based on 13 years of field research at the Minnesota Landscape Arboretum and four years at the Research and Outreach Centres in Crookston and Morris, Meyer recommends the following list of grasses retailers should be selling in the coming season. All are hardy in USDA Zones 3 and 4, excepted where noted. (See the list at the end of this article).


     You may have heard me say recently that if I were going into business for myself, I would specialize in sedges. Many of these are native, versatile and easy to grow. Start with Carex muskingumensis, the palm sedge. Native to the central Great Lakes region of the U.S., this semi-deciduous sedge has attractive foliage that resembles palm fronds. Two to three feet high, it is a taller sedge, dark green in the shade and chartreuse in the sun. It prefers moist soil and can grow in standing water (lakeshores) but I have not seen it in this location. There are variegated and miniature forms of palm sedge, but we have just planted them this year at the Arboretum, so performance in Minnesota is unknown.

     Other sedges to try are: C. pensylvanica, Pennsylvanian sedge, also a Minnesota native to mesic and dry sites, it tolerates full sun and semi-shade, and grows 6-12 inches. C. greyi, Gray’s or mace sedge, grows to two inches, prefers light shade and has interesting mace seedheads.

     There are many small variegated sedges, none of which have been long-term survivors at the Arboretum. These small, mounding sedges are the number one selling grass in Europe and are seen in large mass plantings, just as Liriope is used in southern U.S.

     Little bluestem, Schizachyrium scoparium, is a beautiful native grass. We have some superior selections in our field trials and plan to introduce these within the next few years. This three foot-tall tough grass likes medium to dry soils and full sun. It tolerates a wide variety of conditions and may self-seed. Fall colour is reddish-orange to purple or bronze. Some selections lodge or fall over. It is easily propagated from seed but also very variable from seed. ‘The Blues’ is a light glaucous blue selection from the variety Aldos from the NRCS, which originated in Kansas. ‘The Blues’ will survive in Minnesota, but has lodged in the Arboretum trials.

      Prairie dropseed, Sporobolus heterolepis, likes much the same conditions as little bluestem, medium to dry sites in full sun. It is finer in texture with a low mound of foliage. The fragrance of the flowers resembles coriander, cumin or buttered popcorn. A wonderful native, which is beautiful in the perennial border.


     Or course, feather reedgrass, Calamagrostis acutiflora ‘Karl Foerster’ — the 2001 Perennial Plant of the Year — is a grass everyone already has. It is the most popular grass sold in Minnesota and should be a best seller in 2001. Tolerant of dry or wet sites, it grows vigorously from divisions. Sterile, setting no seed, with its stiff upright appearance, it is a joy to grow and sell. I have noted some decline with the age of older plants, which may show the need for division after five to seven years.

     Everyone should consider the “other” Calamagrostis: ‘Overdam’ a variegated mutation of ‘Karl Foerster’ that is shorter — three feet tall, with white flowers. And C. brachytricha, fall blooming reedgrass, with its vase shape and dense pinkish-green panicles in late September. C. brachytricha may self seed, but not enough to cause a problem. It prefers full sun and is almost as tall as ‘Karl Foerster.’

     Blue oatgrass, Helictotrichon sempervirens, still deserves a place on the list. Hardy, showy blue and neat in form, it flowered more in 2000 than any year previously in Minnesota, but the gangly oat-like flowers are not showy and the foliage is still the primary interest. Native to the Mediterranean, blue oatgrass likes medium to dry, well drained soils and can handle the heat.


     An editor of Better Homes and Gardens called me recently to verify the grass Spodiopogon sibiricus, frost grass, was really a plant. She could not find it in any catalog and needed verification of the name. So, I guess the market is wide open for this grass! Still a favourite for the most “shrub-like” grass, this dense, thick foliage looks like bamboo. Yellow or bronze fall colour is another highlight, but weak stems make this disappear in winter.

     Molinia is a genus with two beautiful grasses that should be sold in Minnesota. The tall form, Molinia caerulea spp. Arundinacea has numerous cultivars, all of which look very similar (to me); ‘Windspiel’ and ‘Skyracer’ are both showy. The six to seven foot-tall leafless culms or stems are so fine, you can see right through them. When the sun catches the stems, you can see the plant, and other times, it is so light, you may miss it entirely. The small form Molinia caerulea ‘Variegata’ is an 18-inch yellow and green striped plant that likes moist soil. Having lost it at the Arboretum, I thought it was not hardy, but it has survived four years in the field trials in Crookston and looks quite robust there.


     Now to Miscanthus, the best seller in the U.S. Gardeners love the big showy flowers and dramatic look of Miscanthus. Many of the 50 cultivars of M. sinensis were planted in 1994 and 1996 at the Arboretum, and final hardiness recommendations have been difficult, since the recent winters have been mild. Variegated forms rank high with the public: ‘Zebrinus,’ ‘Variegatus.’ Morning Light’ and ‘Strictus’ are all favourites. ‘Variegatus’ has the best hardiness of these forms and I would urge all growers in zone 4 to sell it. Only one winter (1989) it died, other years it is a beauty regardless of whether or not it flowers (in early October), but it is not hardy in Zone 3. Other favourites are: ‘Rotsilber’ (redsilver flowers); ‘Klein Fontäne’ (little fountain) both five to five-and-a-half feet tall, with purple flowers in September. ‘Purpurascens’ has been a disappointment some years, dry conditions may reduce or eliminate flowers and fall colour. Older plants need to be divided for best performance; ‘Silberfeder’ (silverfeather) is still the tallest at six to seven feet, reliably hardy Miscanthus for Minnesota. ‘Silberfeder’ may lodge, although some people find this attractive and call it “arching.” I recommend you select one from each of the four groups listed in the table on page 19 for Miscanthus.

     A recent study we did of Miscanthus self-seeding shows it has the potential to be a weed in unmowed areas. We see about a dozen seedlings each year. The variegated types set very little viable seed and are the least likely to cause a problem with self-seeding.

     I was ready to end here, but wait! What about Panicum and Sorghastrum? These are both good bets. Many named superior selections of hardy, ver­satile Panicum are available. ‘Sioux Blue’ is a beautiful Indian grass, six feet tall with shiny bronze flowers that last all winter. Deschampisa, a great grass for the shade, should also be included. It is hard to end the list! As time goes on, more and more grasses will be good sellers for your business. The sophisticated, educated consumer of today is looking for new and different perennials, and ornamental grasses fit the bill very nicely.

Mary H. Meyer’s good ornamental grasses for Minnesota

1. Carex muskingumensis palm sedge
2. Schizachyrium scoparium little bluestem
3. Sporobolus heterolepis prairie dropseed
4. Calamagrostis acutiflora ‘Karl Foerster’ feather reedgrass
5. Calamagrostis acutiflora ‘Overdam’ overdam feather reedgrass
6. Calamagrostis brachytricha fall blooming reedgrass
7. Helictotrichon sempervirens blue oatgrass
8. Spodiopogon sibiricus frost grass
9. Molinia caerulea spp. arundinaceae ‘Windspiel’ or ‘Skyracer’ tall moorgrass
10. Molinia caerulea ‘Variegata’ variegated moorgrass
11. Miscanthus sinensis miscanthus pick one from each group, 3 denotes cultivars hardy in Zone 3
    • variegated: ‘Variegatus’; ‘Zebrinus’ (marginally hardy); ‘Morning Light’ (marginally hardy)
    • short, early flowers 4 ½-inch: ‘Bitsy Ben’; M. oligostachyus
    • medium, early flowers: ‘Klein Fontäne’ ‘Rotsilver’; ‘Graziella’; ‘Purpurascens’ 3
    • tall, later flowers: ‘Silberfeder’ 3; ‘Malpartus’; and ‘Autumn Light’; ‘Giganteous’ 3 (flowers rare; synonym is M. floridulus)
12. Panicum virgatum ‘Rehbraun’, or ‘Rotstrahlbusch’ switchgrass
13. Sorghastrum nutans ‘Sioux Blue’ Indian grass
14. Deschampsia caespitosa tufted hairgrass

Reprinted with permission from the Minnesota Nursery Growers Bulletin, December 2000 edition.