Estimated read time: 4-5 minutes
Larry Sagers Horticultural Specialist Utah State University Extension Service Thanksgiving Point Office © All Rights Reserved
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Fall is the most interesting season for most grasses. The very showy and interesting seed heads emerge in all their resplendent beauty. The colors change from greens to rich reds, oranges, browns and gelds. These stems wave in the wind for an additional charm in the garden.
Of the hundreds of species of grasses, some 150 different types grow as ornamental in our area.
They are highly adaptable to most different soils and require little fertilizer to grow and flourish. The only routine care that they need is to cut them to the ground in the spring. This gets rid of the old foliage and lets the new, attractive foliage reestablish.
After they are established, most need little water and are very drought tolerant. Most are also very tolerant of heat and of full sun. As an added bonus, they get few if any insect pests and almost no diseases here in Northern Utah.
Most grasses are winter hardy but some are tender perennial grasses grown as annuals in this area. The annuals include the red and green fountain grasses and several others. Since these are no longer growing, the focus now on the perennial grasses.
Perennial ornamental grasses are increasing dramatically in popularity as gardeners look for low care, high impact plants. They usually require less care throughout the growing season. Unlike lawn grass, ornamental grasses do not require frequent mowing, watering, and pest control.
When making your evaluations and selections, consider all the plant growth factors. Examine the attractive foliage, the texture, the spring, summer and fall color. Look for those with distinctive plant forms and look for showy flowers or seeds, which make excellent landscape accents or for dried arrangements.
Use grasses as groundcovers, borders, screens or specimen plants. Depending on the species, these grow well around ponds, streams, perennial borders, rock gardens, or naturalized areas.
Ornamental grasses come in a myriad of different sizes, shapes and colors. They range in height from less than 6 inches to more than 14 feet. Some have thin, flexible stems while others have large almost bamboo pole like qualities.
Spread is extremely variable and how they spread is one of the most critical decisions in grass selection. The different types are divided into the bunch forming and the spreading grasses.
Bunch or clump forming grasses spread by tillers. These new plants or offshoots form on the outer edges of existing plants. These are well mannered in the garden and stay where you plant them without invading the surrounding areas.
The spreading or running grasses are great for a lawn but are sometimes a problem when planted as ornamentals. These plants also produce tillers but also produce rhizomes and stolons. These horizontal stems spread in all directions as they stems grow above or below the soil surface.
The invasive qualities of these grasses are a serious drawback to their use. These grasses can quickly take over and exclude all other plants in the area. In severe cases, they can become horrible weeds and become very difficult to eradicate.
If there is a problem with selecting grasses for our area, it is that not many grasses are adapted to the shade. About the only ones that will do well here are the Japanese Forest Grass and Carex siderostica >Varigata=. Most others prefer warmer conditions with much more intense sunlight.
While it is impossible to list all of the grasses that grow well here, I will list a few of my favorites. Keep in mind that you much match these to your growing area if you want them to be successful.
For the large specimens, plant Arundo donax, or Giant Reed Grass. This grows fifteen feet or even taller in our area. Many think it is a bamboo, but it is not. The yellow groove bamboo will get up to fifteen feet in our area. A third tall specimen is the northern pampas grass or plume grass. Erianthus ravennae grows 7-15 feet tall in an upright open clump.
For sheer beauty, look for at some of the many different species and cultivars of Miscanthus. These are variable with some less than two feet tall while others will grow more than eight feet. These are very showy right now because the delicate feathery plumes look great and will continue to add to the garden throughout the winter.
Some of my favorite drought tolerant selections include the Great Basin Wild Rye a Utah native plant. This grows to six feet and survives after establishment without supplemental irrigation. Add to that list the Big Bluestem and Little Bluestem, both outstanding grasses that are native to the prairies of the Great Plains.
Spend some time evaluating and selecting these wonderful plants. Winter might be here but you can warm your heart by focusing on these plants that are ideal assets for local gardens. Few plants are as easy to take care of and yet give so much throughout the season as the grasses.