Ornamental grasses bring beauty, motion, and a soft, romantic look to beds and borders
Born mixers, ornamental grasses belong in the garden, not banished to the outskirts with only each other for company, says Rick Darke, an internationally recognized authority on grasses and author of The Color Encyclopedia of Ornamental Grasses. He points out that these fluid, subtle plants are at their best playing off of perennials, shrubs, annuals, and trees.
“A border composed solely of flowering perennials can be colorfully bland,” Darke says. Adding grasses brings texture, motion, light, and even sound to the garden. More important, grasses are graceful threads that weave all other plants in the garden together, making them look more like family members than a convention of strangers.
Western designers have found beautiful new ways to integrate grasses into the garden. Lew Whitney, vice chairman of Roger’s Gardens in Corona del Mar, California, combines grasses with shrubs in low-maintenance but high-interest foundation plantings, where flowers are clearly secondary to foliage.
The nursery’s demonstration garden is a good example. Grasses with vertical thrust, such as blue oat grass (Helictotrichon sempervirens) and pheasant’s tail (Stipa arundinacea), look like “fireworks erupting between the hills,” he says, when combined with dense, round shrubs like apple green Pittosporum crassifolium ‘Compactum’. Billowing white cascades of ribbon grass (Phalaris arundinacea) and a green carpet of autumn moor grass (Sesleria autumnalis) contribute additional textures, shapes, and colors.
Burgundy-colored fountain grasses, bronze carexes, ultrablue fescues, and bold variegated grasses capture the most attention in nurseries, but some designers prefer more ordinary greens. “Not every plant in the garden should call attention to itself,” says Laguna Beach, California, landscape architect Jana Ruzicka. “You need some respite.” That’s why Ruzicka’s favorites include unvariegated greens such as maiden grass and sheep fescue (Festuca ovina).
Simple grasses are particularly appealing when used in gardens close to wilderness, as is the case with Kelley and Stanton Perry’s home in Laguna Niguel, California, overlooking coastal chaparral. “In this situation, a variegated grass would have been too fussy,” says Carole McElwee, the garden’s designer. “I wanted everything to be very soft and subtle ― mostly grays, greens, and blues ― just like the view.” Despite the formal columns and the bench, this garden feels a bit wild. And grasses are primarily responsible for that mood.
Containers. Ornamental grasses make great companions to potted annuals, perennials, herbs, succulents, and broad-leafed plants. If the container is particularly striking, let the grass go solo ― so it complements its setting rather than competes. Blue lyme grass (Elymus arenarius ‘Glaucus’), for instance, looks dyed to match when paired with a weathered copper pot. The arching shape of eulalia grass (Miscanthus sinensis) mimics the shape of an urn. Bronze carex or blonde feather grass pairs beautifully with rusty iron.
Ground covers. Neat little tuft grasses ― such as carex and festuca ― look good with practically anything. Ruzicka uses green Carex texensis with coral bells and other woodland plants under trees. Santa Monica landscape designer Susanne Jett creates meadows of blue fescue, rosy pink yarrow, and snow-in-summer, and she mixes fescue with aloes and other succulents for a Mediterranean look. (Slightly taller, looser grasses like blue oat grass and autumn moor grass also work.) To make any of these simple grasses look natural, use them in clusters ― they rarely occur in widely isolated clumps in the wild.
Hedges and screens. Grasses 6 feet or taller, like many eulalia grasses, can form barriers, boundaries, and screens that catch the light and move gracefully. Eulalia grass is an outstanding screener, but also try Calamagrostis acutifolia ‘Stricta’ and Molinia caerulea.
Perennial companions. Grasses of medium stature ― 3 to 6 feet ― or low clumping grasses with tall flower spikes all look good with perennials and flowering shrubs. Here are a few combinations that work well.
Blue oat grass (Helictotrichon sempervirens), a metallic blue grass bearing wheat-colored flowers, combined with yellow Mexican tulip poppy (Hunnemannia fumariifolia), euphorbia with chartreuse bracts, orange monkey flower (Mimulus), or true blue Salvia patens.
Feather reed grass (Calamagrostis acutifolia), a deep green, very vertical grass waving feathery plumes of blond flowers, paired with Russian sage (Perovskia), rudbeckia, or tall yarrows like ‘Coronation Gold.’
Mexican feather grass (Stipa tenuissima), a very fine-textured green grass sporting a bleached-blond mane of flowers in late summer, with Santa Barbara daisy, lavender, Salvia greggii, or small agaves. Invasive warning: No longer recommended for California.
Oriental fountain grass, a dense blue-green mound of grass carrying fluffy pink, caterpillar-like flower heads, with ‘Autumn Joy’ sedum, bearded iris, and pink shrub roses.
Pink muhly (Muhlenbergia capillaris), a dark green grass bearing a cloud of pink flower panicles, partnered with asters and smoke tree (Cotinus coggygria) or Dalea capitata and bush morning glory (Convolvulus cneorum).
How to care for ornamental grasses
Weekly irrigation is sufficient for most established grasses, and many get by with considerably less water. Don’t bother with fertilizing ― they look better without it. Leave your chemicals in the garage; pests and diseases rarely affect grasses. To keep plants from looking ratty, cut them back once a year in late winter or early spring when new growth appears at the base. Cut the clumps back to just a few inches above the base. Grasses also need dividing when they outgrow their area or develop bare centers.
Where to buy
Most nurseries sell a variety of grasses that thrive in your area. The following mail-order sources also carry good selections.
Forestfarm, 990 Tetherow Rd., Williams, OR 97544; (541) 846-7269; free catalog within U.S. ($5 in Canada).
Digging Dog Nursery, Box 471, Albion, CA 95410; (707) 937-1130; free catalog.
Heronswood Nursery, 7530 N.E. 288th St., Kingston, WA 98346; (360) 297-4172; catalogs $5-$8.
Plants of the Southwest, Agua Fria, Rte. 6 Box 11A, Santa Fe, NM 87501; (800) 788-7333; free catalog.
The Color Encyclopedia of Ornamental Grasses, by Rick Darke ( Timber Press, Portland, OR, 1999; $49.95; 800/327-5680). Darke, the author and primary photographer for the book, has spent decades researching, growing, photographing, and designing with grasses.
Beware of invasive grasses
Though undeniably beautiful, many grasses need to be used with caution. They produce large amounts of seed, easily dispersed by wind, and have the potential to be invasive. If you live close to fragile wilderness, be especially careful. Choose grasses native to your region, or, before planting, check with county extension offices to see if any ornamental grasses are potentially invasive in your area. Don’t plant giant reed (Arundo donax) in California or the Southwest, jubata grass (Cortaderia jubata) or pampas grass (C. selloana) in coastal California, or green fountain grass (Pennisetum setaceum) in Southern California or the Southwest.