Learn about ornamental grasses, including how to plant and grow them.
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How to Grow: Ornamental Grasses
Many different types
full sun, part sun
Bloom Period and Seasonal Color
late summer and fall in shades of brown, purple, red, and silver
Mature Height x Spread
1 to 6 feet x 1 to 3 feet
native, attracts beneficials, drought tolerant, deer resistant
Ornamental grasses have become all the rage in landscaping circles and there are a wide variety of these grasses that grow well in our region. The key is to select the right ones that are hardy for your area. Ornamental grasses fill many rolls in the garden. They provide a solid backdrop for more colorful perennials. They can compliment other flowers and shrubs with their interesting leaf texture and color and flower heads, Ornamental grass” nodding flower heads also provide beauty and movement in fall and winter to provide interest in an otherwise bleak winter landscape. Ornamental grasses also provide habitat for birds and insects making them key players in an ecologically oriented yard.
Where, When and How to Plant
Ornamental grasses are best purchased as transplants from local garden centers in spring or obtained from a friend’s garden as divisions. Plant grasses from spring to early fall in full or part sun to form the best flower heads on well-drained, compost-amended soil. Space the plants according to their growth habit, from 1 to 3 feet apart.
Keep newly planted grasses well watered after planting. Once established, ornamental grasses are drought tolerant. Apply a layer of compost each spring to encourage their growth.
Regional Advice and Care
Not all types of ornamental grasses are hardy throughout New England. Also, ornamental grasses vary widely in their mature sizes and ability to spread. Ornamental grasses need little care once established. They can be divided in spring to create more plants or keep their growth in bounds. Leave the flower heads to enjoy in fall and winter and cut back ornamental grasses in early spring before new growth emerges. Some grasses will self sow readily and volunteers should be thinned out in spring.
Companion Planting and Design
Plant ornamental grasses with other late summer and fall blooming perennials, such as Russian sage, rudbeckia, asters, and sedum or with evergreens and shrubs. Tall ornamental grasses, such as feathered reed grass, can be grown into an informal hedge to screen an unsightly view. Mounding types, such as hakone grass, make great additions as a ground cover or edging plant.
“Karl Foerster” feathered reed grass grows 5 to 6 feet tall producing purple-colored flower heads that fade to tan. Hakone grass is only hardy in southern New England. It grows into a 2-foot tall mound with green and white grass blades. Northern sea oat grass is a native grass that grows 3 to 4 feet tall with beautiful oat seed heads that turn brown in fall and are good for flower arrangements. Oat grass self-sows readily. Switch grass is another native that offers airy plumes with good fall color. Blue fescue grass only grows in 1-foot tall mounds with blue foliage and tan flower heads.
Excerpted from my book, New England Getting Started Garden Guide.
Everyone should grow some grass. No I don’t mean lawns, or that “other” grass, but ornamental grass. Ornamental grasses have become a staple fixture in many residential and commercial landscapes. While they are a getting a bit over used in my opinion, I still love them. The big draw of ornamental grasses is their flower heads in fall and winter. These beautiful grasses not only add color and texture to a bleak landscape, they add motion. When a breeze blows through a stand of oat or reed grass you can almost see the wind’s shape and intensity. While many ornamental grasses are easy to grow, you have to be selective about which ones you plant in our climate. Here are some of my favorites.
Karl Forester reed grass has pink plumes in summer that last into fall. This grass grows 4 to 5 feet tall so makes a statement when plant en mass. Northern Oat grass grows 3 to 4 feet tall and in fall produces flattened, oat seed heads that sound great in a breeze and look beautiful cut as a dried flower indoors. One word of caution, oat grass can self sow readily and become weedy in the garden. Japanese Silver grass or Miscanthus sinensis grows 3 to 6 feet tall in tightly packed clumps and has pink or red flowers. A nice low mounding grass is called blue fescue. It grows only 8 inches tall in mound shape with attractive blue-green leaves and airy flowers. It’s great along the front of a border. One tall ornamental grass you’ll see along roadsides and ditches that shouldn’t be brought into the landscape is Phragmites or common reed grass. It’s an invasive and chokes out other native plants.
Now for this week’s tip, it’s time to bring in tender potted herbs such as rosemary. Place them in a shady spot outdoors to acclimate to low light, then bring them into a bright window indoors and keep the soil moist, but not over watered.