Redtwig Dogwood Offers Vibrant Winter Color

When I first began gardening, the only dogwood I knew of was our native dogwood tree, with it's spring-time show of delicate pink or white blossoms. Yet the dogwood genus contains a huge variety of plants, ranging from woodland ground covers, to shrubs, to trees that grow to forty feet. While many of these make excellent additions to the home landscape, none are more versatile than the redtwig dogwoods. These multistemmed shrubs are garden performers all year long and provide real drama in the winter landscape with their colorful branches.

There are two species of redtwig dogwoods, the Tatarian dogwood (Cornus alba) and the Redosier dogwood (Cornus sericea). Their care, cultural requirements and effect in the landscape are nearly identical. They are easily grown and transplanted, adapt well to dry or extremely moist soils, and prefer full sun to part shade. In spring, they have flat, cream-colored flower clusters that are followed by ivory or blue berries which provide food for birds. They have a rounded shape and spread by suckers or underground stolons, especially in moist soil, forming colonies with colorful stems in winter that have great ornamental appeal.

The Redosier dogwood is native to North America and is very useful in the New England designed woodland garden, where it spreads naturally in colorful swaths. It is often planted in groups in the shrub border or massed on slopes for erosion control. The Tatarian dogwood is native to northeastern Asia. In the home landscape, it is typically planted in groups, often with needled evergreens as a background for its colorful winter stems. Both dogwood types grow vigorously in Zones 3-7, but neither does well in the heat and humidity of the south. Noteworthy varieties are C. sericea 'Baileyi', which grows 6-9 feet high with foliage that turns reddish-purple in fall and has a winter stem color of dark red; and C. alba 'Bud's Yellow',which grows to 6 feet high, has reddish fall foliage and a winter stem color that is an unusual bright yellow.

All redtwig dogwoods offer multi-season interest, but there are some that add more drama to the home garden than others. I love the cultivars with variegated leaves: their bright foliage commands attention, spring through fall. In my garden, I grow two variegated C. alba cultivars. I use 'Elegantissima', which has greenish-grey leaves edged in white, to brighten up a shady spot in my shrub border. In early spring, its red stems are complemented by a nearby grouping of yellow-flowering trout lilies (Erythronium), whose green leaves are mottled with the same dark reds of the dogwood. In summer, 'Elegantissima' mingles effortlessly with ferns and other perennials, such as hosta (H. 'Winfield Blue', H. 'Shade Fanfare' and  H. 'Dream Weaver'), a small blue grass (Festuca glauca 'Boulder Blue'), coral bells (Heuchera 'Coral Dream') and epimedium.

I have grown the variegated C. alba 'Ivory Halo' in a large planter on my deck since 2008. This may be the year it gets planted out in the garden, but I am sold on its performance, beauty and adaptability as a year-round container plant. I will definitely plant another to grace my deck. Or maybe this time I'll try a new cultivar, like 'Silver & Gold', which has green and silver foliage and cheery yellow stems in winter.

Redtwig dogwoods require pruning to retain the winter effect of vivid branch color: the brightest color occurs on the newest branches. Prune out old, colorless branches that are more than 2-3 years old; cut them back close to the ground to stimulate bright new growth.

The redtwig dogwoods offer year-round beauty in the suburban landscape. They are especially valued for their vibrant winter stem colors that are stunning when framed by the snow.  Redtwig dogwoods can be purchased at many local nurseries and from online sources such as forestfarm (www.forestfarm.com).

By Joan Butler

Japanese Stewartia: A Multi-Season Beauty

asily grown and beautiful in all four seasons, Japanese Stewartia earns its keep in the garden year-round. Valuable as a specimen tree in the lawn or shrub border, it offers long-term impact in the landscape with its summer flowers, brilliant autumn color and exfoliating bark that provides dramatic winter interest.

Japanese Stewartia (Stewartia pseudocamellia) is perfectly suited to the suburban landscape. In the winter, its beautiful bark and sinewy, muscular trunk and branches create an unbeatable effect. The bark has the look of camouflage gear, smooth with patches of rich gray, tan and terra cotta.

The tree has a pyramidal shape, and young branches have a slight zig-zag pattern of growth with small pointy buds at their tips. Its architectural beauty is especially dramatic when the tree is outlined with a fine tracery of snow. Japanese Stewartia is one of the few trees that bloom in the summer, producing a succession of camellia-like white flowers with gold anthers for more than two weeks in July. In the fall, it dazzles! Its lustrous green summer foliage turns to shades of yellow, red and reddish-purple. When back-lit by the sun, it is breathtaking.

A bit of advice about Japanese Stewartia: be sure to plant it where you can see it all year long – you won't want to miss a thing! Mine is planted across the yard from my kitchen window so I can enjoy it easily in every season. The tree is now large enough to fill the view from the window. In the summer, it adds to the serene beauty of my shrub border. It is underplanted with shade-loving, long-lived perennials: golden Japanese forest grass (Hakonechloa macra 'Aureola'), Hosta (H. 'Liberty', H. 'Kabitan', H. 'Kiwi Blue Baby'), shiny European Ginger (Asarum europaeum) and assorted Epimedium cultivars. Add some coleus and angel-wing begonia and you have a heart-stopping moment in the garden. In the fall, the Stewartia's blazing foliage takes center stage. And in the winter, its patchwork bark pattern stands out against the snow and clear blue sky. This naturally well-shaped tree is one of the most desirable small- to medium-sized specimen trees around.

How can a tree that offers so much require so little? Plant Stewartia in well-drained humus rich soil in a sunny spot with some afternoon shade and you will be rewarded with years of stunning beauty. It reaches 30-40 feet at maturity and has no major disease or pest problems. It is somewhat pricey, but the distinct contribution it provides to the four-season landscape makes it a garden gem. Stewartia can be purchased locally at many nurseries, including Weston Nurseries and through mail order sources such as RareFind Nursery (www.rarefindnursery.com).

By Joan Butler

Christmas Fern: Fronds in the Snow

My first introduction to the Christmas Fern came at a garden club flower arranging workshop. Everyone brought greens from their gardens to supplement a ‘supermarket bouquet’, and I was amazed when one of the members produced a mass of shiny, lance-shaped fern fronds. Ferns from the garden in February? In New England? I had to get the name of that fern and add it to my shade garden collection.

As it turns out, the Christmas fern (Polystichum acrostichoides) is not as exotic as I had thought. It is one of the most common ferns in eastern North America, found from Nova Scotia west to Minnesota and south to Florida and eastern Texas. Given its wide range, it is an admirable plant, surviving deep freezes in the North and dry heat in the South. Moreover, throughout its distribution, it's often the most common species. If you want to know the name of just one wild fern, you'll get the most mileage from knowing this one.

Ferns were among the first plants to inhabit the earth. They are more than twice as old as the first flowering plants, and their method of reproduction is very primitive. They reproduce not by seed but by microscopic spores. There are more than 12,000 species of ferns in the world today. Ferns enjoyed huge popularity in Victorian times (the craze was called “Pteridomania”) when they were collected and their image was used to embellish pottery, furniture – everything from christening presents to gravestones and memorials. In New England, the Christmas fern was very popular during the Christmas season for wreath-making and other yuletide decorations – hence its common name. Some also believe that the name “Christmas Fern” came from the shape of the pinnae (individual leaflets), which resemble a Santa’s boot or a Christmas stocking.

Christmas ferns are particularly accommodating garden plants. They are adapted to a wide range of conditions, from very dry to moist, and prefer fertile, humusy, well-drained soil in full to part shade. Once established, they will even survive periods of drought. I was particularly happy to learn that they will grow under mature trees - even Norway maples with their huge, thirsty surface roots. They virtually mulch themselves; old fronds fall to the ground in spring as new fiddleheads emerge. They are resistant to pests and diseases and are seldom bothered by deer. Christmas ferns grow slowly to form dense clumps, which can be divided into several plants in the spring. Given adequate soil and moisture, they will also multiply through spores to form a nice colony.

Christmas ferns grow two to three feet tall, and are easily recognizable in a woodland setting since they are one of the few green plants poking through a blanket of snow. Lush new spring growth begins early, as soon as the winter snows melt. Fiddleheads appear sometimes as early as the mayapples, trilliums and other woodland wildflowers. The new fronds are an attractive silver to light green in color, maturing to deep, glossy green. As the new growth emerges, the old fronds begin to quickly wither away.

I was happy to receive ten healthy clumps from a friend’s lakeside garden in the Hudson River valley. Her garden is set on a steep slope to a lake - a perfect habitat for Christmas ferns, which perform a soil conservation function. Their fronds are semi-erect until the first hard frost, after which they recline to the ground, effectively holding in place fallen leaves so that they become soil on the slope. The ferns can be planted in masses or as single specimens that will contrast in form with other shade-loving perennials such as hostas, lily of the valley, hellebores, bleeding hearts and epimidiums.

 For the home gardener, the Christmas fern offers year-round enjoyment, bringing a hint of the lush green forest to the backyard, and an elegant, long-lasting addition to holiday arrangements. 

Winterberry Holly Is A Beacon in the Garden

or brightening the winter landscape, nothing can compare with winterberry holly. Its bright red berries are a visual stoplight in garden settings and in our New England woodlands and marshes. Winterberry is a tough native shrub that adapts to a wide range of growing conditions. In the wild, it can be found thriving in wet, boggy locations but also does well in drier sites in the woodland and home garden. Typically, it reaches heights of 6-8 feet and spreads slowly by “suckering” to form small thickets. It grows in full sun to part shade, with berry production best in full sun. The profusion of shiny berries that cover its branches from fall through winter make it a stand-out anywhere it is planted. 

Winterberry holly is part of a diverse genus (Ilex) that includes evergreen and deciduous hollies. Most people are familiar with the evergreen varieties, with their spiny leaves and red berries that are staples of holiday decor and floral arrangements. The deciduous varieties are less well-known, although probably everyone has noticed them and wondered about their identity. Winterberry holly (Ilex verticillata) is the most common of the deciduous hollies. It is native from Newfoundland west to Michigan and south to Maryland and West Virginia. The summer foliage is a rich dark green. Autumn foliage is yellow and is not considered particularly showy. The berries that color up after the first frost  are the real show-stoppers here. And, as an added bonus, the berries are a nutritious food source for birds.

There is no shortage of winterberry cultivars. “Red Sprite” and “Winter Red” are particularly favored for their prolific production of large red fruits. Also popular is “Sparkleberry”, an Ilex verticillata hybrid with a heavy fruit set and smaller berries. If you want to try something different, “Winter Gold” produces berries that are a spectacular peach-salmon color. There is even a cultivar with variegated foliage, the uncommon “Sunsplash”, with leaves that are streaked with yellow.

As is typical of most hollies, male and female flowers are found on different plants and only the female plants produce berries. If you want berries, you must have both sexes present within a distance of 50 feet of each other; one male will fertilize 6-7 females. The male must bloom at the same time as the female. Common male pollinators are “Jim Dandy”, which will fertilize “Red Sprite” and other early-flowering types, and “Southern Gentleman” which will fertilize “Winter Red”, “Winter Gold”, “Sparkleberry” and other later-flowering types.

In my garden, I grow the cultivar “Cacapon”, which I have planted in two different locations. In the mixed shrub border out back, “Cacapon” has become a six-foot tall thicket covered with red berries that I value for their winter show and contrast against the evergreens. In the front foundation plantings, it is growing as a small tree, nearly eight feet tall now, with wonderful dark grey branches and red-orange berries. Light pruning in the spring improves berry production in both locations.

If you are looking for something to brighten your winter gardens, look no further than winterberry holly. Best planted in spring and fall, winterberry can be purchased locally at many nurseries, including Weston Nurseries, and through mail order resources such as RareFind Nursery. (www.rarefindnursery.com).

By Joan Butler

Luecothoe's Painterly Foliage for the Winter Garden

Foliage, texture and shape all play an important part in choosing a plant for the winter garden. One of my favorite plants for winter landscaping is Leucothoe fontanesiana ‘Girard’s Rainbow’ – a graceful evergreen shrub with variegated foliage on red-streaked branches. I first fell in love with the plant visiting my brother in Seattle about 12 years ago. He took me to a huge nursery that was stocked with plants that flourished in the Pacific Northwest but were not widely available here at that time. I could not resist the leucothoe, and brought a small specimen in a 4” pot home with me. Planted under a native dogwood next to my front porch, the leucothoe has thrived and bloomed reliably every year.

 Although it looks somewhat exotic, luecothoe is native to North America, at home along the banks of creeks or massed in front of shrub borders. While there are many varieties of leucothoe, ‘Girard’s Rainbow’ is the most widely available variegated cultivar. Its shiny foliage emerges white, pink and copper on arching stems, maturing to green streaked with cream. Some plants also display burgundy-edged foliage, particularly in winter. This shrub is a slow grower that reaches 3-5 feet tall and wide. Its white, fragrant, and somewhat pitcher shaped blooms are born in clusters similar to blueberry and lily-of-the-valley flowers. Although it blooms prolifically in mid-spring, there is so much foliage that the visual display is not particularly showy.

 This evergreen is easy to grow and quite versatile as a garden shrub. A woodland native, it prefers a site in part shade with deep, acid, well drained soil amended with plenty of organic matter. It needs little or no pruning, but may be rejuvenated if needed by cutting back all the way after flowering.  Mine is pruned whenever I have to create a flower arrangement or just want to bring some greenery indoors– the variegated foliage is beautiful on its own and complements many flowers. Once mature, leucothoe is also easily propagated by snipping off branches that have touched the ground and rooted. I now have many offspring of the Seattle leucothoe growing in my garden and in those of my friends.

 Despite its great looks, leucothoe 'Rainbow' is not very well known, so it is often overlooked by both homeowners and professional landscapers. It makes an ideal plant in borders, foundation plantings or in combination shrub plantings. It is very effective when planted against an evergreen background, and brightens up shady spots. Leucothoe is a natural companion plant to rhododendrons, and is often used to "loosen up" the tight feel that hollies and boxwood give to the landscape. It also looks great surrounded by hostas, ferns and hellebores, and makes a beautiful statement in the winter garden.

Hellebores - Stars of the Winter Garden

The longer I garden in Metrowest Boston, the more I appreciate the importance of winter interest in the garden. While evergreen trees and shrubs provide structure in the garden, it’s wonderful to see the emergence of a perennial flower bud from the groundshortly after Christmas – the hellebore! Sometimes referred to as 'ChristmasRose' or 'Lenten Rose', hellebores are the stars of the late winter/early spring garden. Plants generally bloom between December and March in cultivation, though some begin earlier, and others continue into April and May, particularly in gardens with colder spring climates. Nearly every garden has a spot for hellebores, and the plants will thrive in many different environments.Still, they remain unknown to many gardeners despite their toughness, beauty, hardiness, and wonderful habit of blooming in winter when most other plants remain dormant.

The majority of hellebores are deep-rooted, stout plants, with thick, shiny, green foliage. The large leaves may persist through winter, but not all plants are wintergreen in all climates. The plants grow 12-18” in height, and gradually increase indiameter to form large clumps with masses of nodding flowers. Once established,most hellebores make drought-tolerant, particularly if given some dappled shade in locales of long, hot and/or dry summers. Although hellebores are almost invariably sold as shade plants, in most garden conditions they will perform their best if given some sun. They prefer rich soil with plenty of humus and a mulch of shredded leaves or bark, and are deer resistant.

Hellebore flowers have five petals, and some species resemble wild roses, which is why theircommon names include “Christmas rose” and “Lenten rose”. They do not belong tothe rose family however, but to the buttercup (Ranunculaceae) family. In the past decade, as hellebores have increased in popularity, hybridizing has vastly improved the color range of the flowers from near-blacks, deep purples, andslate grays through rich reds, cherry-blossom pinks, yellows, pure whites and soft, creamy lime greens. Many have dots or blotches of a contrasting color around their centers. New hybrids also include those with double flowers (Helleborus “Royal Heritage Mix”;). In my garden, the flowers remain on the plant for almost three months, turning from their original hue to a soft shade of green over time. and those with their flowers turned up (Helleborus “Ivory Prince”;).

In a lightly shaded garden, hellebores look beautiful combined with pulmonarias, ferns, and lamiums. In my own garden, I like to place hellebores where I will easily see them in winter and early spring – near the driveway and walkways to the house.A grouping of nine hellebores plays center stage in a circular bed next to the driveway, surrounding a silver gazing globe on an ornate pedestal. From November to April, the hellebore foliage and flowers are the only visibleplants in that bed. As spring unfolds, the foliage of coral bells, astilbes, cinnamon ferns and variegated hostas gradually fill in, and by the time that the hellebore flowers have faded, the other perennials are in their prime.

Some of the most common species of hellebores are Helleborus niger, the “Christmas Rose”, which blooms in winter; Helloborus orientalis, the “Lenten Rose”, which blooms in early spring; Helleborus occidentalis, Helleborus argutifolius, and Helleborus foetidus. The new color forms are hybrids of Helleborus orientalis and areusually labeled as Helleborus x. hybridus.

Hellebores may be purchased in local nurseries, and are also available from mail order sources such as Pine Knot Farms (www.pineknotfarms.com), and Heronswood Nursery (www.heronswood.com).