Long leaves of green, and tall waving plumes. A beautiful privacy screen, a refreshing wash of greenery, and so easy to maintain. Ornamental grasses are one of the easiest ways to transform a modest bit of property into a lush garden setting.
(Editor's Note: This article was originally published on June 22, 2009.)
At least 100 varieties of ornamental grasses grow throughout the world: some small, some huge, some sprawling, some neatly mounded, some evergreen, and some seasonal. The one thing these plants have in common is that they are beautiful and, once established, very easy to maintain. Other positive aspects of grasses include:
Before choosing a grass for your landscape, determine whether you want a cool season or warm season grass. Cool season grasses begin growth early in the spring and often remain semi-evergreen over the winter. During a drought, they will go dormant if not watered; this is not fatal, but the resulting brown foliage is not attractive. Most of these grasses are clumping, which means they will need to be divided as the years pass. Some popular cool season grasses are:
Warm season grasses do not begin growth until soil and air temperature have stabilized. These grasses do not remain green during winter, but do provide beautiful contrast and texture to a garden with their dried leaves, stalks, and plumes (which are also a source of food for over-wintering birds). Most of these grasses are also clumping and will need to be divided to keep them healthy, but not as often as cool season varieties. Additionally, in spring before new growth begins, the old stalks must be cut back to about 4 to 6 inches. Popular warm season grasses include:
Another consideration before choosing a grass is to determine the final location as it relates to your other garden beds. Some grasses form rhizome and are often referred to as “running” grasses. These can be invasive and quickly get out of control in a landscape design. One method for containment is to plant the grass inside a large 5-gallon plastic container with the bottom cut out. However, eventually as the plant matures, rhizomes might still find their way out the bottom and come up somewhere else. Be cautious when using these varieties--they are better suited to forming privacy screens or property borders where they are free to expand. Blue lymegrass (Elymus arenarius), Cordgrass (Spartina), and Ribbongrass (Phalaris arundinacea, aka Reed canary grass, Gardener’s garters) are aggressive, but very attractive.
Caring for Ornamental Grasses
Once established, most ornamental grasses need very little attention, except for spring cleanup and division, when required. A newly planted clump of grass should be watered thoroughly and often through the first season; after that, their root systems have bored deeply into the soil and they will need very little, if any irrigation. During extreme drought conditions, some species will need additional water.
In spring, well before the weather warms and the new growth begins, cut the dried stalks back to about 6 inches. This can also be done in the fall after the foliage has dried. Small grass clumps are easy to cut back, but the larger ones often require tying the foliage with cord or a bungee, then sawing through the base. Any way you do it, you’ll have a bit of a mess--one of the only drawbacks to ornamental grasses.
When a mature clump begins the spring with only an outer circle of new growth, it’s time to divide the clump. The empty center of the clump is a combination of dead roots and foliage, and the plant will not re-grow from this area. Dividing a large clump of grass takes a lot of effort and strength, and sometimes a sharp axe! Clumps of about 2 feet in diameter can be divided into two new plants; clumps measuring 3 to 4 feet across will provide four to five new plants.
Dig the entire plant out of the ground before cutting it into sections. Clean each section, removing the dead material, then replant. Water well through the first season.
Add some waves of green to your own landscape and enjoy it for years to come.
Resources North Carolina State University College of Agriculture and Life Sciences, Hort on the Internet
University of Illinois Extension, “Maintenance of Ornamental Grasses”
Toni Leland has been writing for over 20 years. As a spokesman for the Ohio State University Master Gardener program, she has written a biweekly newspaper column and is the editor of the Muskingum County MG newsletter, Connections; she currently writes for GRIT, Over the Back Fence, and Country Living magazines. She has been a gardener all her life, working soil all over the world. In her day job, she scripts and produces educational DVDs about caring for Miniature Horses, writes and edits books about them, and has published five novels.