Coniferous evergreens provide a hardy backdrop for displaying plants at the Denver Botanic Gardens. Photo courtesy of Wikimedia.
Living screens are as versatile as they are varied. They hide the neighbors, block ugly views, provide backdrops and create garden rooms.
Originally, though, screens were used to hem in livestock. When humans made the leap from hunter-gatherers to start an agrarian lifestyle, they prevented animals from wandering by using living screens left behind as they cleared the land for planting. In ancient Roman times, the practice became more structured as farmers planted their own shrubs to mark property lines and keep animals in line.
Jump forward thousands of years and living screens gained traction as aesthetic as well as utilitarian elements in European gardens, where some hedges date back 300 years or more. The tradition was introduced in the United States and took root on the large estates built along the eastern seaboard.
“Even now on the West Coast hedging material is not as popular as on Long Island or New England, where there’s more of an European influence in landscapes,” said Jason Bizon, sales manager for Carlton Plants outside of Dayton, Oregon. “The use of European hedges was brought over in Colonial days and set the standard.”
Hedge installed as a landscaping element. Photo by Lori Scott Landscape Design
East and west
To this day, landscapes on the east side of the country echo the traditional European aspect with privet (Lugustrum), yews (Taxus), beech (Fagus), and hornbeam (Carpinus). In the west, arborvitae have long — some think too long — been the industry staple.
“People hate arborvitae,” said garden designer Lori Scott of Portland, Oregon. “But the thing about arborvitae here is that there’s no other plant that grows tall and skinny that’s evergreen, that’s available year-round and super cheap. Cheaper than building a fence. It’s got everything, but we’re sick of them.”
We may be tired of them, but most people are hard-pressed to come up with many alternatives to arborvitae besides Leyland cypress (Cuprocyparis leylandii), laurel (Prunus spp.) and Irish yew (Taxus baccata), which Scott loves but points to its high price tag as a drawback.
Lauren Hall-Behrens, owner of Lilyvilla Gardens in Portland, Oregon, also takes up the case for arborvitae. “I don’t feel snobby about plants that are overused. It looks like a green wall and I think that’s valuable.”
To go beyond arborvitae requires some thinking outside the box, Scott said. She admires is Viburnum tinus ‘Robustum’ because it’s such a go-to plant with evergreen foliage, fast growth, winter blooms, and navy blue berries. In maturity, this viburnum gets up to 12 feet and is 6 feet wide. Its life expectancy wanes anywhere below USDA Hardiness Zone 7, though. “Too bad it’s difficult to find,” Scott said, “Because it would be super popular in the areas where it’s hardy.”
In her own garden, Scott designed a curved boxwood (Buxus sempervirens) screen that she keeps sheered to about 4 feet, though could let grow to its adult size of 12 feet or more. She’s been happy with these Zone 5 plants since Day One.
Also in her own garden, she put in a row of Oregon grape (Mahonia aquafolium). “It’s an awesome backdrop,” Scott says of the Zone 5 plant that reach heights up to 10 feet. “It has bright yellow flowers in March and gorgeous blue berries in summer. The birds fly in and out, in and out. It’s important ecologically, too.”
Green mountain boxwood root development. Photos courtesy of InstantHedge
Typical versus exotic
Jay Sanders, sales manager at KG Farms in Woodburn, Oregon, said laurels make up their bread and butter. Skip laurel (Prunus laurocerasus ‘Schipkaensis’), the hardiest at Zone 6, is usually headed to the mid-Atlantic states. Portuguese (Prunus lusitanica), the most unique with a darker green leaf and red stems, goes over well in the Northwest. The glossy green foliage of English laurel (Prunus laurocerasus) sells in California where it doesn’t suffer in the heat.
“Laurels are very rapidly growing plants, which is good and bad,” he said. “It gets rid of the neighbors fast, but you’ve got to trim these plants. English laurel takes at least two prunings a year; skip laurel takes one.”
Osmanthus heterophyllus ‘Goshki’ makes Sanders short list of good screen plants. It’s a Zone 6 plant that gets 6 to 8 feet tall and has eye-catching evergreen foliage that starts red and turns to green with splashes of cream. “They’re a lot bigger than most people think,” he said. “They look cute in the gallon pot, but they do get big and they take well to trimming.”
Along the same lines is Pyracantha × ‘Teton’, a plant soon to take up residency on the availability list of InstantHedge, a new nursery with a new-to-the-U.S. concept. According to owner Brent Markus, the pyracantha has good berry set and, like the osmanthus, is “great for keeping the critters out, including the two-legged variety.”
Markus started InstantHedge after consulting with Quick Hedge, a nursery in The Netherlands that sells ready-to-go screens. He’s now growing 53 miles of hedge material featuring plants from 18-inch boxwood to 5-to-6 feet tall arborvitae. Most of his stock so far is evergreen, but Markus has plans to add more deciduous. Of particular interest is ‘Flame’ amur maple (Acer ginnala), which he said has a good seed set, is fast-growing at 2 feet a year and a good size at 12 feet tall by 4 feet wide, with handsome fall color. It’s hardy down to Zone 3.
Markus is a fan of growing some unusual plants, but said he’ll always grow what the market demands.
“We want to grow hedge varieties that are household names,” said Markus, who has a degree in landscape architecture from Cornell University. “I’m going to grow skip laurel because that’s what people want.”
But deciding on inventory is not an exact science, Markus noted. So he’ll be growing some things that the public isn’t necessarily asking for, like Cornelian cherry (Cornus mas), a small tree to 20 feet. In early spring, it bears a mass of yellow flower clusters before it leafs out, followed by red berries in summer.
“It would be difficult to dethrone European beech in terms of a deciduous screen,” Markus said. “It is elegant and sleek and has amazing longevity. But Cornus mas has so many cool features. Once landscape architects and designers start using it, everyone will.”
It’s hard to beat boxwood in terms of sales, though. Markus said he’s shipping pallets and pallets of boxwood back East, including more than 300 units to a single estate in North Carolina. “We’re getting queries from estates for 600 hedge units. That’s five and a half truckloads.”
At Whitman Farms, owner Lucille Whitman suggests some unusual candidates for screening, including Ribes sanguineum, especially the more upright forms like ‘Pulborough Scarlet’ that drips with red flowers in early spring, and Callicarpa bodinieri ‘Profusion’, with its multitude of eye-popping purple berries. Both are about 8 feet tall, though can get bigger, and would need pruning to shape them into a formal screen.
“I’m excited for the time to come on the West Coast where we follow some of the landscapes of the East Coast and use more screening and hedging materials,” Bizon said. “In summer, you can have shade and privacy and in winter you let the light in.”
Screens versus hedges
Bizon makes a distinction between a hedging tree, which you can’t see through, and a screen, which you can. Screening trees would typically be planted on center with a gap from the ground of anywhere from 36 to 48 inches. Hedging trees have to be sheared at least once a year and may be limbed up as little as 4 to 6 inches.
“If you want privacy in winter and light in the winter, go with a screen,” Bizon said. “But if you want year-round privacy, use a hedging tree.”
Examples of screening trees are upright oaks (Quercus) such as ‘Regal Prince’, ‘Kindred Spirit’, ‘Green Pillar’, ‘Skinny Genes’ and Crimson Spire™ Oak (Quercus robur × Q. alba ‘Crimschmidt’). Others are Liquidamber styraciflua ‘Slender Silhouette’ (sweetgum), European aspen (Populus tremula erecta) and flowering crabapples (‘Emerald Fire’ and ‘Purple Fire’).
A side-by-side view of Crimson Spire™ Oak (Quercus robur × alba ‘Crimschmidt’) in 2009 and in 2018 at McMenamins Edgefield in Troutdale, Oregon. Photos courtesy of J. Frank Schmidt.
Nancy Buley, communications director for J. Frank Schmidt & Son Inc. in Boring, Oregon, will raise her hand for oaks, as well. Crimson Spire™ Oak, she said, stays super narrow but reaches 40 feet tall, has dark red foliage in fall and is hardy to Zone 4. Its adaptability means it can be used in a wide variety of locations, most commonly in the Midwest, Rocky Mountain states, California and across the Pacific Northwest. Russet-brown leaves hold on well into December or January, longer than other fastigiate oaks. A good example of a hedge made of Crimson Spire™ Oak is between two parking lots at McMenamins Edgefield in Troutdale, Oregon. Streetspire® Oak (Quercus robur × alba ‘JFS-KW1QX’) is a newer cultivar of the same cross as Crimson™ Spire. It loses its leaves earlier, and completely around Thanksgiving.
It’s hard for Buley to cut her list down, but she puts at the top Parrotia persica ‘Persian Spire’ and ‘Parkland Pillar’ birch (Betula) for a smaller screen and, in addition to the oaks, ‘Mountain Sentinel’ quaking aspen (Populus tremuloides) and ‘Armstrong’ and ‘Red Rocket’ maples for larger.
‘Persian Spire’ is low- and dense-branching compact tree that grows fairly quickly to 25 feet and is hardy to Zone 5. It was discovered as a seedling at John Lewis Propagation Nursery (JLPN) Inc. in Salem, Oregon.
“It’s a sweet little tree,” Buley said. “It’s got smaller leaves than the species, is columnar and pretty refined. It holds that margin of purple on its new foliage into summer and has fantastic fall color.”
Discovered in Manitoba, Canada, and introduced by Bailey Nurseries, ‘Parkland Pillar’ birch (Betula platyphylla) has the white bark customers love, is low-branched, dense-foliaged with attractive, dark green leaves that crinkle round the edges and turn golden in fall. This New Editions plants climbs up to 40 feet and is very hardy — down to Zone 3. ‘Mountain Sentinel’ quaking aspen is also a Zone 3 tree. It only gets 8 feet wide but soars up to 35 feet.
These Zone 4 maples get big, too, up to 40 feet and only 12 feet wide. ‘Armstrong Gold’ is more dense than ‘Armstrong’ and glows orange-red in fall. ‘Red Rocket’, as the name implied, explodes in red.
Stars of the screen
“Columnar sells,” Buley said. “Narrow trees are really popular right now. It’s a function of limited space. Residential lots keep getting narrower. Homes are closer together. There’s a big demand.”
The pros of screens are many — privacy, less wind and noise pollution, crime deterrent and wildlife haven — but the cons are few. In fact, the only disadvantage is keeping some of the more vigorous plants within bounds. Not a bad tradeoff.
Kym Pokorny is a garden writer with more than 20 years of experience writing for The Oregonian (Portland, Oregon) and other publications. She is currently a communications specialist with Oregon State University Extension Service. Kym can be reached at [email protected].
