The conifer lowdown. Ground-hugging evergreens cling to challenging sites while bestowing color and texture on landscapes

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1 Sporting light green needles that turn an attractive yellowish green in winter, Pinus sylvestris Hillside Creeper accents rock gardens or foregrounds of shrub borders. Photo courtesy of rare tree nursery The conifer lowdown Ground-hugging evergreens cling to challenging sites while bestowing color and texture on landscapes By Elizabeth Petersen Conifer ground covers? I love them! said Brent Markus. Markus, a landscape architect, owns Rare Tree Nursery in Silverton, Ore., and operates Markus Specimen Trees Inc., a design firm in the Chicago and Boston areas. I just completed a project in Brookline, Mass., where we used Picea pungens Glauca Prostrata to create a sea of blue water down a hillside, he said. When homeowners consider conifers, they usually envision towering trees rising above layers of other plants. But low-growing conifers with spreading or prostrate habits should also be a part of the picture. Like their upright relatives, groundhugging conifers bestow color and texture to landscapes, and they solve a range of problems on challenging sites. Since their needled forms spread horizontally, they can ramble down banks, creep over rocks and soften hardscapes. Their presence combats erosion and controls weeds, too. Many conifer ground covers take the harshest conditions, from baking sun to heavy loads of snow and bitter cold. Most require little maintenance, and need minimal inputs of water and fertilizer. Plus, they have tough constitutions that resist assaults from disease, insects and deer. Design-wise, they come in vari- december 2013 DIGGER 19

2 the conifer lowdown ous colors (green, blue and yellow); textures (from the sharp look of spruce to soft hemlock); and sizes (for small, medium or large spaces). Spruce up with Picea The powder blue Colorado spruce Picea pungens Glauca Prostrata can develop a leader, growing into an informal, irregular tree with a spreading skirt. The customer can also keep it low by pruning the leader. Hardy to USDA Zone 3, it takes sun and cold as its branches spread out along the ground to about 6 feet in 10 years. Conifer expert Don Howse recommends P. pungens Glauca Procumbens. This selection has the same bright blue color as Glauca Prostrata, but is not inclined to send up a leader or develop upright growth. Its spreading, undulating nature makes it an excellent alternative to junipers. For a slow-growing carpet of green foliage, Markus recommends P. pungens BLOOMING NURSERY Picea omorika Kamenz is a hardy spreading spruce with a distinctive two-tone look. Short branches are covered with needles, green on top and silver beneath. Photo by Randall C. Smith, courtesy of Iseli Nursery Pinus sylvestris Albyn Prostrata, as the cultivar name suggests, is a prostrate form of Scots pine. It grows to only 1' tall but spreads along the ground over time to 6' wide. Photo by curt kipp 20 december 2013 DIGGER

3 Mesa Verde. Its name translates into green table, which accurately suggests the verdant, flat growth that can reach 4 feet in 10 years. Plus, it has remarkable tolerance to adverse conditions. Markus suggests an old variety of weeping Norway spruce, P. abies Formanek, as another leaderless, low-growing form. It will crawl along the ground to create an incredible mound of foliage, he said. The dark green prostrate conifer has a dwarf growth rate, about 3 6 inches a year, so it maintains a more confined footprint. Formanek can also be staked to achieve some height and then allowed to gracefully drape and wander. For a carpet of golden spruce in part shade, Markus likes P. abies Vermont Gold. This incredibly low, Farm Store golden form of bird s nest spruce will Main Street reach about 9 12 inches tall and 7 feet wide in St. 15 Paul, years. Oregon Sandy Dittmar of Iseli Nursery, a wholesale grower in Boring, Ore., offers a spreading Serbian spruce, P. omorika Kamenz, that produces a distinctive two-tone look. The slow-growing, adaptable spruce has short needles that simultaneously show both green on the top and silver beneath. Kamenz complements the form of a bank or slope with cold hardiness to USDA Zone 4. Ever-popular pines Pines produce ground-hugging forms, too. The old variety Pinus banksiana Schoodic is becoming more popular lately, Markus said. Dense and prostrate, the Jack pine selection spreads only about 6 inches a year on all sides, but does a good job draping down a wall or spreading out in a low mass on a bank. Ornamented with emerald green Our needles team has and the numerous knowledge cones, the slow-growing and experience pine takes to assist cold to you USDA Zone in 2 making and performs sound well decisions. in full sun. This variety likely evolved as a protection against the harsh elements, Markus said. Other pine varieties that Markus endorsed for great ground-covering David & Patrick Marion Ag stocks the largest and most complete inventory in North America. Custom Blending Dry Fertilizers Liquid Fertilizers Main Office Organic Amendments 7746 St. Paul HWY Fertilization Programs St. Paul, Oregon Pest Management Testing & Analysis Equipment Painting Seed Cleaning Sand Blasting Animal Feed Our team has the knowledge and experience to assist you in making sound decisions. Farm Store Main Street, St. Paul, Oregon Home of the St. Paul Rodeo Custom Blending Dry Fertilizers Liquid Fertilizers Organic Amendments Main Office Fertilization Programs Pest Management Testing & Analysis Equipment Painting Seed Cleaning Sand Blasting Animal Feed 7746 St. Paul HWY, St. Paul, Oregon december 2013 DIGGER 21

4 wet the conifer & wild lowdown capability are selections of P. sylvestris, the Scotch pine. P. sylvestris Albyn Prostrate is a sturdy, spreading form with dark green needles and a silver or blue cast. Hardy to USDA Zone 3, this pine can gradually conform to the shape of a sunny slope or drape over a retaining wall. Tough and adaptable, the slow grower will grow to be about 3 feet wide in 10 years. P. sylvestris Hillside Creeper is similar to Albyn Prostrate but provides a greater spread, creeping along the ground to 8 feet or more over time. It hugs the ground better than Albyn Prostrate and is particularly effective on a bank or hillside. Also, its structure is more exposed, which adds character, and it is lighter in color, taking on a yellow-green hue in winter. P. sylvestris Repens is the slowest growing of the three. Dark green to glaucous green needles and an irregular form give it an alpine look. Many pendulous conifers grow The soft, short needles on branches of Tsuga mertensiana Elizabeth flare out, looking like fine blue bottle brushes. Photo by Randall C. Smith, courtesy of Iseli Nursery Abies procera Glauca Prostrata, Prostrate Blue Noble Fir, has attractive steel blue foliage. Its texture blends into the landscape, but can be balanced by one or two finer or coarser trees or shrubs for an effective composition. Photo courtesy of rare tree nursery 22 december 2013 DIGGER

5 Premier Supplier of Nursery Products perfectly flat or have wave-like rambling foliage if they re not staked, Markus said. Take, for example, P. strobus Stony Brook, a prostrate, weeping white pine with light gray contorted branches. For sun or part shade, this pine grows about 9 12 inches per year and is hardy to USDA Zone 3. P. mugo is one of the most climateadaptable plants available, Dittmar said, and P. mugo Valley Cushion is an excellent choice for cold parts of the country. The compact, dense pine grows very slowly and stays low and flat. Reddish, new buds complement the short, medium green needles. Selected at the North Willamette Research and Extension Center, this cultivar is extremely hardy to USDA Zone 2. Shipping Materials - Stickers, shelves and pallets made to your specs, pallet repair boards, shipping gates, tilt sticks, used pallets Packing Supplies - Shrink wrap, banding Planting Stakes - Multiple sizes available Treated Lumber - Multiple sizes available SW Highway 18, McMinnville, OR Hardy hemlock Dittmar also recommended hemlock cultivars with ground-covering forms. In her opinion, Tsuga canadensis Cole s Prostrate is an underutilized plant with delicate green needles and really cool silvery bark that gets gnarly with age. Branches on the slowgrowing dwarf hemlock spread straight out and drape over or around rocks or walls. The Zone 4-hardy ground cover works well in a partly shady site. T. heterophylla Thorsen s Weeping can create a presence combining vertical and horizontal features when staked and allowed to sprawl into a broad skirt. Versatile and hardy to USDA Zone 4, this hemlock grows quickly and establishes itself when young. Dwarf T. mertensiana Elizabeth has sturdy, horizontal branches with soft, short, blue-green needles. Although branches mostly stay close to the ground anyway, the plant can be kept consistently flat by pruning out any upright shoots. Native to mountains along the Pacific coast, Elizabeth prefers plenty of moisture, excellent drainage and protection from hot, dry conditions. Jumpin junipers It s no wonder junipers are among the most ubiquitous of ground-cov- december 2013 DIGGER 23

6 the conifer lowdown Often referred to as Blue Rug Juniper, Juniperus horizontalis Wiltoni is an excellent evergreen ground cover for a multitude of different soil types and sites. It is often used in rockery plantings and flower beds where it can create a cascading effect as it spreads out. Photo by Maggie Neely 24 december 2013 DIGGER

7 ering shrubs. As a genus, Juniperus is among the most adaptable of plants. It boasts the largest range of any woody plant in the cool, temperate Northern Hemisphere of North America, Europe and Asia. Widely used and frequently abused by pruning to restrict their spread, junipers are consistent sellers, nevertheless. Industry standards Juniperus horizontalis Wiltoni and J. horizontalis Blue Chip sell unfailingly year after year, said Joel Johnson of Eshraghi Nursery in Hillsboro, Ore. Once established in the landscape, they will save you time and money on maintenance of weeding and watering, he said. The long, trailing branches of Wiltoni cover large spaces, as the common name Blue Rug Juniper indicates. Berries and plum tones in winter add to the interest of the reliable, low mat that thrives in places as cold as USDA Zone 3. Other junipers offer versatile groundcovering options, coming in shades of blue, yellow and green and sizes suited for small, medium and large spaces. Among yellow varieties, dwarf J. horizontalis Mother Lode is one of Iseli s most popular junipers. Found as a sport of Wiltoni at Iseli, the extremely flat conifer boasts bright golden-yellow foliage in spring and summer. The cold of winter brings on rich burgundy/ plum undertones. A slow spreader, it performs best in hot, sunny conditions with high humidity, such as is found in Atlanta, Dittmar said. Markus values Mother Lode, too. The perfectly prostrate golden juniper has tremendous utility in the landscape because of both its gold color and its flat-as-a-sheet form, he said. For an electric chartreuse ground cover, J. h. Limeglow has a spreading, vase-like form and feathery, juvenile foliage that holds its brilliance and resists sunburn. J. chinensis Daub s Frosted develops bright yellow frosting over blue-green older growth in spring. Reliably colorful and hardy to USDA Zone 4, it transi- BARK FOR CONTAINER MIXES Various Sizes Available ASK ABOUT OUR CUSTOM SOIL BLENDS! 1275 Bailey Hill Road Eugene, OR Office: Fax: Contact Rex for pricing at ROOTING COMPOUND Soluble Concentrate Continued excellence from our family owned company for over 30 years WOOD S ROOTING COMPOUND Our unique formula uses only the highest quality ingredients which results in instant absorption of both IBA & NAA to your cuttings. 3 Convenient Sizes: 4 oz. / Pint / Gallon Call Today For A Distributor Near You P.O. Box 327 Wilsonville, OR SIZES! december 2013 DIGGER 25

8 the conifer lowdown Using Our Pots Can Also Lift Your Bottom Line! High Quality Competitively Priced Injection-molded Nursery Containers Sizes #1 #25 Call For Information and Free Samples Pringle Road SE (Salem, OR) tions to a striking bronze in winter. In shades of blue, J. conferta Silver Mist has needle-like, viridian foliage with broad, white stomatal bands that add a silvery sheen. A spreading form with intermediate growth and USDA Zone 5 hardiness, Silver Mist tolerates many conditions, including poor and sandy soils, but not soggy sites. J. squamata Blue Carpet has prickly needles, too. The low, spreading plant has an intermediate growth rate and is hardy to USDA Zone 3. With a lower profile than the familiar Blue Star, it is an excellent choice for banks, slopes and other challenging sites. One-of-a-kind carpeting conifers Another conifer ground cover favored by Markus for its brilliant blue fir foliage is Abies procera Glauca Prostrata. It has a horizontal layering habit but may send up leaders with age. Tolerant of sun or part shade and hardy to USDA Zone 6, the slow-growing Noble fir can be kept low by removing any upright growth. An emerging new cultivar recommended by Markus, Larix eurolepis Lulu was found as a seedling of L. decidua Varied Directions. It grows much more slowly and stays completely prostrate, Markus said. Imagine soft, larch foliage with incredible fall color and Zone 3 hardiness wow! The very low, spreading larch becomes a carpet of copper in fall. Sequoia sempervirens Kelly s Prostrate is a very popular variety that has a flattened bird s nest spruce form. Horizontal sprays of bright green foliage project from the center of this mounding dwarf redwood. A wonderful ground-covering plant that is a true gem for its rarity and form, Markus said. For sun or part shade, the slow-growing plant is hardy only to USDA Zone 8. Elizabeth Petersen writes for the garden industry and teaches SAT/ACT test prep at She can be reached at gardenwrite@comcast.net or satpreppdx@comcast.net. 26 december 2013 DIGGER