Orange County Master Gardener Plant Sale 9/28/14 10/19/14. Evergreen Perennials

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1 Evergreen Perennials

2 Carex 'Evergold' Origin. This sedge, first described in 1914 by the Japanese botanist Takenoshin Nakai, is native to dry forested areas and rocky slopes at mid elevations on the main island of Honshu in Japan. There has been much confusion surrounding the cultivar and numerous names have been applied to it. It was formerly considered a Carex morrowii selection. Garden use. With regular watering, can be massed or grouped in the woodland garden or border. May be used to edge a woodland path, grown in low spots or along ponds or streams, or used in the rock garden or spilling over a rocky slope. It is beautiful as a spiller in containers. This is one of the most popular variegated sedges. Bloom. Brownish flowers in late spring are insignificant. Many people prefer to remove them when cutting back the plant in spring. Foliage. Grass-like, arching, variegated leaves (1/2" wide to 12" long), creamy yellow with dark green borders. Habit and vigor. A dense, drooping, clump-forming sedge holding its nice appearance year-round. Siting. Site in locations sheltered from strong winds. Culture. Easily grown in medium to wet soil in part shade, but tolerates dry shade with occasional watering. Foliage color is best in bright shade or with morning sun. Plants tend to languish in full shade and will suffer in extreme heat. Cut back to the ground in late winter. Clumps can be divided in early spring. Problems. No significant insect or disease problems.

3 Dryopteris 'Autumn Fern' Origin. Autumn Fern (aka Japanese Shield Fern) is native to woodland hillsides and mountain slopes in Japan, China and Taiwan. Garden use. This fern is particularly nice when grown in woodland or Japanese gardens and is is a good choice for tough conditions like dry shade or part shade under large trees. Unlike many other ferns, it will not go dormant in a dry summer. It can be massed for use as a ground cover. Like all ferns, it looks good with other woodland perennials likes hostas, hellebores and epimediums. Because of the unique coloration, this fern also works well with both needle and broadleaf evergreens, hydrangeas, and other dark-leaved plants like abelia and flowering quince. The copper new growth in fall is a nice complement to aging oakleaf hydrangea flowers. Bloom. none Foliage. The common name 'Autumn Fern' refers to the beautiful copper-pink color of the newly emerging fronds, which glow against the backdrop of the shiny, dark green, mature fronds. The sori, which are produced in fall, are bright red. Habit and vigor. This is an arching, vase-shaped, clumping fern to 2' tall and as wide. It is a tough, low-maintenance plant once established, equal to our native Christmas fern in persistence and ease of culture. Siting. Site in locations sheltered from strong winds to protect the fronds. Culture. The Autumn Fern thrives in neutral to acidic, loose, richly organic soil and light to full shade (plants can take direct morning sun if the soil is moist). Prefers consistently moist soil. Mulch around the plants with dead leaves in the fall, to help conserve moisture in summer. Clumps can be divided every 3 4 years, in early spring. Problems. No serious insect or disease problems. A rugged and easy-to-grow plant.

4 Helleborus 'Pine Knot Select' Origin. Helleborus x hybridus (aka Helleborus orientalis) is native to mountainous areas of Northeastern Greece, northern and northeastern Turkey and Caucasian Russia. Garden use. Helleborus x hybridus have beautiful, bold, textured foliage and look great with ferns, hostas, and Solomon's seal. They make a nice woodland groundcover and offer flowers in February- March when your garden desperately needs some color. Site near a window for easy winter viewing. Awards. Hellebores were chosen as the Perennial Plant Association s 2005 plant of the year. Bloom. Plants are seedlings and therefore not identical. However, each individual will retain the same color and pattern over its lifetime. Flowers may be any color or pattern (solid, picotee, spotted or blotched). You can cut the flowers, leaving about ¼ inch of stalk behind each bloom, then float the blooms in a bowl of water, where they will last several weeks. Foliage. Tough, palmate, sometimes rugose and shiny, dark forest green. Habit and vigor. Plants perform best if not divided and will have large root systems at maturity. Although you can cut back old foliage just before bloom to better appreciate the flowers, this is detrimental to plant vigor. Because stored carbohydrate in the old foliage is used to make new foliage, plants will perform best if old foliage is not removed until the new foliage has expanded to full size. Siting. Protect from winter winds. Plants do well on hillsides or slopes, and a slope aids viewing the flowers, which nod downward. Site these where they will stay for many years, since plants resent being disturbed. They will grow in full shade under large deciduous trees as long as they receive full sun while the trees are bare. Hellebores do not regulate dormancy, so a northern exposure will protect them from inappropriate growth/bloom that could lead to subsequent cold damage. Culture. Easily grown, best in organically rich, humusy, mildly acidic, well-drained soils in part to full shade. Hellebores are drought-tolerant but because buds are formed in summer, stress such as withholding food and water can reduce blooms in winter. Hellebores don t need division, but if propagation is desired, do so in spring after the ground has thawed, just before bloom. Problems. No serious insect or disease problems. A rugged and easy-to-grow plant.

5 Stachys 'Big Ears' (aka 'Helen von Stein') Origin. The species is native to Turkey, Armenia and Iran. Garden use. This is a wonderful plant for edging, massed in the front of the border garden, or in containers. Bloom. 'Big Ears' does not flower, so it will not take over your yard and the clumps always look neat. Foliage. Leaf shape and texture resemble a lamb's ear, hence the common name. 'Big Ears' is noted for its particularly luxuriant silver-green foliage, which is more than twice the size of other lambs ears, up to 10 inches long and very thick and soft. The leaf color is noticeably less silver than other lambs ears and easier to work into a garden color scheme. Leaves are evergreen in a mild winter, but will look tatty or die back after a harsh winter. Rake in the spring once cold weather is past to remove the dead foliage and plants will quickly renew. Habit and vigor. Dense rosettes form a mat approximately 8" off the ground. This cultivar is more of a clump-forming plant and requires division to create a groundcover. Plant 12-18" apart for use as ground cover. Siting. Our winters have been more severe recently, so a protected spot (eastern exposure or next to masonry, drive, sidewalk, patio that can emit radiant heat) might help keep the foliage more evergreen. Culture. Easily grown in average, dry to medium, well-drained, lean soil (don't fertilize). Well-drained soils are essential in order to combat potential rot problems. 'Big Ears' appreciates some light afternoon shade, but too much shade may impede leaf drying and promote the onset of disease (see Problems section below). Avoid overhead watering. If mid-summer foliage decline occurs, pick off damaged leaves as needed. Drought-tolerant once established. Divide in fall or early spring when necessary (if plants become woody in the center) or to fill in bare patches. Problems. Even with well-drained soils, some summer die-out may occur if high humidity or moisture on foliage is persistent. 'Big Ears' has better resistance to heat and to these problems than the species and many other cultivars, and is a good selection for our area. Summer leaf rot, when it occurs, is usually the bottom foliage and is hidden from view, so the plants still look good. Plants usually look their worst after a hard winter, not in summer.

6 Deciduous Perennials

7 Agastache 'Grape Nectar' Origin. Agastache is a genus of about 30 aromatic species native to central and eastern Asia, Mexico, and the United States. Garden use. The compact size of this cultivar makes is a great addition to smaller containers or the front of the border. The heavily branched stems also make this a nice cut flower. This cultivar is one of the Nectar series bred for floriferousness. Bloom. Lovely bi-colored lavender and purple flowers, very nice citrusy scent. Deadhead to prolong bloom until frost. Flowers are edible, try some! Hummingbirds love the nectar, and the flowers attract beneficial insects as well. Foliage. Green foliage, sturdy flower stems. Habit and vigor. This plant is new to us. It has a compact, upright habit. We assume it is vigorous, because all agastache are. Siting. Plants must have excellent drainage to survive the winter. In addition, do not cut the plants back until spring growth has begun. We are not sure about the genetics of this cultivar, but for Western agastaches, water can freeze in the cut stems and cause crown damage leading to death. Culture. Average garden soil that drains well, acid to neutral ph. Do not fertilize the first spring after planting. In subsequent years, fertilize once in early spring with a layer of well-rotted compost. Overfertilizing, especially with nitrogen, will result in a lot of nice foliage but no or little bloom. Use just a thin mulch and don't overwater established plants. Divide in spring if desired, but because agastache often resent division, cuttings may be a better way to propagate. Problems. Few insect problems. Mildew can affect the leaves during dry summer weather.

8 Gaura 'Whirling Butterflies' Origin. The native range of Gaura lindheimeri is from southeastern Texas east into Louisiana and south into northern Mexico. Awards. The species received the Royal Horticultural Society's Award of Garden Merit in Garden use. Gaura is a tap-rooted plant that tolerates heat, humidity, some drought and poor soils. 'Whirling Butterflies' has a more compact habit and is more floriferous than the species, with brighter white flowers. Excellent in containers and for cutting. Bloom. Pink flower buds and 4-petaled snow white flowers (1" diameter) which appear in long, terminal, wand-like panicles above the foliage over a very long late spring to autumn bloom period. Flowers open only a few at a time, and dance in the wind like butterflies, hence the cultivar name. Foliage. Basal mound of narrow, finely textured, dark green leaves, sometimes spotted with maroon. Habit and vigor. The overall habit is a compact, clump-forming, vase-shaped perennial with wiry, arching red stems. The long, thin flower stems tend to become leggy and flop, particularly when grown in rich soils. Plants often benefit from close planting or support from adjacent perennials. This is not a 'neat and tidy' plant, so if those attributes are important, please look at our other offerings. Siting. Plants must have excellent drainage to survive the winter. Site carefully because tap-rooted plants do not transplant easily. Culture. Best grown in sandy, loamy, well-drained soil in full sun. Good drainage is essential. Remove spent flower spikes to prolong bloom. Plants may be cut back in late spring by 1/2 to control size. Although the species will self-seed, this cultivar is sterile, so self-sown seedlings will not appear. Division is rarely necessary but may be done to yield more plants. In spring or fall, dig out small, newer offsets from the edge of the clump. These sections will not yet have formed tap roots if they are young. Problems. No serious insect or disease problems. Root rot may occur in heavy, poorly drained soils.

9 Peony 'Early Scout' Origin. 'Early Scout' (Auten 1952) is a hybrid between a fernleaf peony and the herbaceous peony 'Richard Carvel'. Garden use. This is a wonderful peony of a different type not a large, scented flower for cutting, but a dainty cutleaf that is best used in a rock garden or a planting bed with other low-growing perennials. It will be out of place in a peony bed, both dwarfed by other peonies and with a different bloom cycle it can bloom before other peonies even have buds. Awards. 'Early Scout' has received both the American Peony Society (APS) Gold Medal, the ultimate award for flower and plant beauty, and the APS Award of Landscape Merit, a new award for peonies that need no flower support even in rainy, windy weather, display superior bloom excellence and presentation, and perform reliably year-to-year across North America's peony growing regions. Bloom. Bloom is very early. The blooms are dark red singles on sturdy stems, opening relatively simultaneously nestled in or just above the foliage. Bloom is therefore intense and showy, but not as long-lasting as for some peonies. The blooms are evenly spaced over the upper half of mature plants, creating a nice symmetric look. Foliage. One of the strong assets of this peony is the beautiful, dense, dissected foliage, which drapes to the ground and remains attractive through the growing season. Habit and vigor. At maturity the plant should be wider than tall. It is supposed to have stoloniferous roots, so may continue to widen with age. Plants establish quickly and increase rapidly, with a nine-year-old plant maturing to 50 stems and a width of over 36 inches. Siting. Like any peony, 'Early Scout' needs winter chilling. It is best sited with a northern or eastern exposure, away from structures that radiate heat such as house walls, driveways, patios, or masonry walks. Peonies need 6-8 hours of full sun but flower color will be fresher with some afternoon shade. Culture. At maturity peonies have a large root run, sometimes more than 4' wide and 18 deep in a well-aerated soil. Prepare the soil widely and well, fortified with both organic matter and mineral nutrients. In heavier soils raised beds are generally advantageous. Plant shallowly, with the bud eyes no more than 1 deep, or your peony may not bloom. While peonies do not need division to remain productive, you can propagate by division if desired.

10 Salvia 'Black and Blue' Origin. Salvia guaranitica is native to Brazil, Paraguay and northern Argentina. It is a tender perennial or subshrub that exhibits a bushy, somewhat open habit with upright, branching, square, dark green stems typically growing 3-5 tall. Garden use. This large woody perennial can be used as a hedge, as a filler for the back of the border, or in very large containers. It offers a flower color that is rarely seen in the garden: truly vibrant cobalt blue, hooded blossoms with contrasting near-black calyces and stems. Bloom. Black and Blue features deep cobalt blue flowers with black calyces. Flowers appear on axillary and terminal spikes to 15 long over a long summer to fall bloom. Hummingbirds LOVE the flowers, and they also attract butterflies and bees. Deadheading will prolong the bloom time. Foliage. Wrinkled lime green leaves (2-5 long) create a vibrant focal point even when the plant is not in bloom and complement the flowers beautifully. When bruised, the foliage has a very mild aroma that has very little if any anise scent. This looks nice behind something with a softer look. Habit and vigor. This is a vigorous perennial that will run, so put it with other vigorous plants and use division to contain if necessary. Siting. 'Black and Blue' is reliably hardy here without any special treatment. Culture. For best display, plant in full sun. In partial shade, it will stretch and the habit will be more open. 'Black and Blue' prefers fertile, average, evenly moist, well-drained soil, preferably an organically-rich loam. It is moderately drought tolerant once established. Divide in early spring if desired. Problems. No serious insect or disease problems. Susceptible to downy and powdery mildew, but this does not seem to be an issue here.

11 Ornamental Grasses

12 Panicum 'Heavy Metal' Origin. This species is native to prairies and open ground, open woods, and brackish marshes from eastern Canada to central and eastern US and south to Central America. Switch Grass was an important component of the tall-grass prairie that once covered much of the Great Plains. Garden Uses. Accent, group or mass, low screen. Perennial borders, wild gardens, native plant gardens, prairies, meadows or naturalized areas, water gardens/bog gardens, raingardens. This outstanding selection forms a stiffly upright clump of powdery-blue leaves, bearing airy heads of tiny green flowers in late summer. Leaf tips turn burgundy in the fall. Usually attractive in the garden all winter long. Flowers are good for cutting, fresh or dried. Drought tolerant once established. Bloom. Foliage is topped in mid-summer by finely-textured, pink-tinged, branched flower panicles which hover over the foliage like an airy cloud. Panicles turn straw-yellow as the seeds mature, fading to beige in winter. Seed plumes persist well into winter providing visual interest as well as food for birds. Foliage. 'Heavy Metal' features metallic-blue foliage. Leaves turn yellow in autumn, and the tips may turn burgundy. Foliage fades to tan-beige in winter. Habit and vigor. The upright, columnar form is an outstanding feature of this cultivar, especially because the vertical form is typically retained without flopping throughout the growing season and into winter. Clumps are typically up to 3' tall (to 5' when in flower). In more northern areas, switch grasses are sometimes stoloniferous, but in southern areas like NC, they grow strictly as clumps and are well-behaved garden plants. Culture. Easily grown a good grass for beginners. Tolerates a wide range of soils, including dry ones, but prefers moist, sandy or clay soils. Tends to flop in rich soils. This grass is notable for being both drought-tolerant and tolerant of temporary flooding, making it a good rain garden species. Generally best in full sun. It will grow in part shade, but begins to lose its columnar form in too much shade, growing more openly and possibly falling over. Cut back clumps to the ground before new growth begins but after the cold weather has passed. Growth begins later in spring than for many other warm-season grasses like miscanthus or pennisetums. Clumps are easily divided in spring. This grass does not come true from seed. Problems. No serious insect or disease problems. Some susceptibility to rust, particularly in hot, humid summer climates, but this does not seem to be an issue here.

13 Pennisetum 'Cassian' Origin. The species is native to Asia and Australia. 'Cassian' was selected by Kurt Bluemel and named for German horticulturalist Cassian Schmidt. Garden use. Fountain grass is one of the best and most versatile grasses for the home landscape, offering three seasons of interest, dependable performance and a graceful fountain-like form. The flower heads are attractive in fresh and dried flower arrangements. 'Cassian' is a dwarf that works well in tight or small spaces, borders, and perennial beds. It also makes a nice urn planting. The mounding, flowing form can be used to soften hardscaping or angular designs, and the leaves and plumes impart motion to the garden, catching the slightest breeze. It can be used as a specimen, but is especially effective as a mass planting. Cassian is also exceptional in that few seedlings are produced, so flowerheads can remain on the plant to be enjoyed without fear that it will overrun your garden. Bloom. 'Cassian' produces whitish-green bottlebrush blooms with a pink tinge in July. Blooms persist well into September. Similar in appearance to 'Hameln', 'Cassian' blooms about 2 weeks later and holds its seed heads for a longer period. Foliage. Foliage is a nice medium green in spring and summer, changing in October to a beautiful mix of gold and orange with red highlights. The fall color is an outstanding asset of this cultivar. In the winter, the straw-colored foliage looks lovely coated in frost or dusted with snow. Habit and vigor. Hoffman's nursery, a large local grower, found 'Cassian' to be hardier than the smaller dwarf, 'Hameln', after our harshest North Carolina winter. Siting. 'Cassian' is especially lovely when backlit by the early morning or late afternoon sun. Culture. Pennisetums prefer rich loamy soil with good drainage and full sun or light shade. They are a bit more demanding than miscanthus or panicums in their culture. They will grow in rocky or sandy soil as long as it remains fairly moist, but resent having "wet feet". Propagate by seed or division. Problems. Fountain grass has no known pest or disease problems.