Ornamental grasses: high visibility, low maintenance
These grasses require little effort, but make a big statement. It's no wonder they're catching on.
"Try them - you'll like them," I argued six years ago.
"Well maybe we could work in a few," replied Dr. Bruce Branham, who was then director of the Hancock Turfgrass Research Center at Michigan State University in East Lansing.
Actually, persuading Branham to go with ornamental grasses wasn't such a hard sell. He knew about their outstanding visual impact. However, there was little budget for maintenance, and once we established the beds, the garden would have to get by on minimal care.
Fortunately, ornamental grasses tend to be low-budget plants to maintain. Plus, many are big, bold and beautiful - maybe just the ticket to attract attention from the buildings and parking area - almost a mile away. The beds might need mulch and a little cleanup each spring but relatively little maintenance the rest of the year. So, I thought we might be able to pull this off.
Six years later, the garden is going great. It's easy to see from the buildings and has attracted quite a bit of attention. In fact, the grasses were so well received that we were asked to add a few thousand square feet of beds around the main research facility. The new gardens have won praise from golf course superintendents, landscape managers and others who visit the facility.
Ornamental grasses sell themselves when given a chance.
Ornamental grasses - a "new wave" in landscaping Ornamental grasses have caught the public's eye the past few years, and with good reason. They are bold, full of texture and movement, and give a new, exciting look to gardens and landscapes. Grasses love light, and full sun is the key to success. Not only do most ornamental grasses perform better in light; they look better with light - in the morning, at noon or at sunset.
You will also find that superior ornamental grass selections are relatively trouble-free and require minimal maintenance - certainly compared with many herbaceous perennials.
For the beginner, all tall grasses seem to look alike. Some look no better than a clump of Kentucky bluegrass in the spring. I'm often asked how to tell the good guys from the bad guys. This can be a problem, but not with the grasses I suggest below.
I suggest that you start simply. Plant a few of the following grasses where you will have ample opportunity to see them grow and develop the first year. You'll be rewarded when they start to show off.
High visibility and low maintenance The ornamental grasses in the table below give high visibility and have low maintenance requirements - a perfect combination.
These bold grasses compete well with weeds, yet never become weeds themselves. These are all clumping grasses that spread slowly from a central crown. With a couple of exceptions, these selections should perform well in most of the United States.
Many landscape managers have been slow to adopt ornamental grasses because they did not know which grasses to plant, or perhaps they feared that the grasses would become maintenance nightmares. This is not the case for the grasses discussed in this article. All have great ornamental value. Planted together, these grasses should provide outstanding flowers from June to October in most parts of the United States - even longer in the mildest areas.
Using grasses in the landscape These grasses are big and bold - equally useful for large mass plantings or for the special touch as individual specimens. Pennisetum spp. are a bit smaller than the rest but still lend themselves to massing and are interesting specimens. Tall purple moor grass makes a fantastic see-through screen. Solid leaves rise to about 3 feet with tall, with airy flower heads 6 to 8 feet high that sway in the wind, making a great view along a pathway. Most Miscanthus species will form impenetrable screens, useful for defining spaces in a landscape.
All of the grasses combine well with perennials for added color and contrast. Choose perennials that match the cultural requirements of grasses - low-maintenance, dependable types (see table, page Golf 5).
Maintaining grasses - Pruning. Once you establish grasses, the only required yearly maintenance is to cut them down in the spring. The actual timing depends on your location. Cutting too early will limit the ornamental value in the winter. However, if your site is little used in the winter, you can remove the foliage in the fall with no harm to the plants. In spring, if the foliage has begun to grow you are pruning too late. In Michigan, the perfect time is usually in April. Farther south and west, February and March may be better times to prune.
Using hand shears, a spin trimmer or even a chain saw, cut the grasses as close to the ground as possible. Leave less than an inch of the old shoots showing above the soil line. Removal of last year's growth makes good sense. It allows more light to reach the center of the plant where the new shoots are freshly emerging. The increased available light increases the number of developing shoots and accelerates plant growth.
Severe pruning will reduce the occurrence of the "doughnut" effect, where the center of the grass dies out and new growth occurs only from the outer ring of the living plant. I have been able to maintain healthy clumps for years without division, in part because I prune the clumps as closely as possible. This goes for all the grasses suggested above.
- Water and fertilizer. Compared with turfgrasses, ornamental grasses require relatively little water or nutrients. In the first year or two, apply some balanced slow-release fertilizer in the spring and some timely irrigation if drought conditions prevail. However, once ornamental grasses are established, fertilize and irrigate sparingly, if at all. The grasses suggested here can tolerate extensive drought, at least under northern conditions. In hotter, more arid regions, some supplemental water may be necessary for grasses to look their best.
- Diseases and pests. We have had few pest problems with our ornamental grass plantings at Michigan State University. In the winter, we sometimes have troubles with voles, which eat the roots and crowns during the winter months. If plants pull right out of the ground in the spring when you are cutting them back, voles are probably the culprit. We have found that traps can reduce vole activity. Plus, if individual grass clumps have suffered from voles in the past, we often cut them back in fall rather than waiting until spring. This removes winter cover (though an inch or two of snow is all voles seem to require).
Mealy bugs are reportedly becoming a pest on Miscanthus in the South and East. Also, I recently have been hearing reports that scale has been found on certain Miscanthus species. When you cut your grasses back in the spring, look under the soil line for any evidence of scale. We have not yet had trouble with mealy bug or scale at Michigan State University, but it pays to check.
On occasion, we have observed Japanese beetles swarming in mass on the taller grasses. However, these chafers do not seem to harm the ornamental grasses the way they do turfgrasses and other types of ornamentals. Any feeding on the leaves is not likely to be detrimental to the plant.
Most ornamental grasses have tough leaves and are not particularly palatable to deer. Plants readily recover in those instances when nibbling occurs. Miscanthus leaves are sharp enough to cut skin and tongues and are essentially deer-proof.
Ordering grasses Ornamental grasses are usually easy to obtain locally. If you are beginning, I advise you to purchase the cultivars I've listed here. Do not accept unnamed cultivars - they are often produced from seed and in some cases make unacceptable landscape plants. For instance, seed-propagated Panicum virgatum is essentially a weed, while the suggested cultivars are well-behaved garden plants.
Wholesale and mail-order nurseries are easy to find on the web by performing a search using the genus and species of your desired grass. Depending on your budget, you can start with plugs, 1 gallon or even larger sizes. We generally start with plugs, even in landscape situations. Plugs are inexpensive and grow relatively quickly to size, though the larger grasses may take two or three seasons before attaining full size. Whatever the starting size, try some ornamental grasses this season - you will like them.
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