Planning and Planting for Winter Beauty

Five ways to brighten gardens with color and texture during the dormant season.

When it comes to garden design, we tend to plan for only three seasons. Perhaps nostalgia guides us: memories of glorious lilacs on Mother’s Day, resplendent hydrangeas mid-summer, or maples going out in a blaze of fall glory to mark the season’s end. We gravitate toward showy plants that dazzle us with their displays and invoke memories of past favorites. Too often, the winter season is an outlier or an afterthought in our landscape

The local nurseries supplying our plants also have some influence, and we’re lucky to have excellent garden centers here on the Vineyard. However, many home gardeners like to purchase plants in bloom for immediate gratification, so that’s what the nurseries tend to stock. Alas, few homeowners think ahead to the long, cold winter months, so home gardens may end up with some traditional evergreens and not much else dedicated specifically to winter. But with a little planning, research, and consultation with plant professionals, you can add trees, shrubs, and grasses that will enliven your landscape throughout the winter season.

I remember my November arrival on the Vineyard some ten years ago. Rather than the height of the gardening year, it was the time known in the plant world as the dormant season. A saving grace for me is that I love tree architecture, branching patterns, and bark. I like to see trees respond to their immediate environment, standing resilient, a living testament to the passing of time. Having now settled into a gardening life and home on the Vineyard (surrounded by oaks), I realize that adding color to my winter world was not only essential, but inspirational.

1. Winter Bloomers

My gardening life – as the director of the Polly Hill Arboretum in West Tisbury, continuing the great horticultural experiment begun by founder Polly Hill in 1958 – has been enriched by meeting interesting new friends and plants alike. Within the diversity of the plant world are horticultural miracles, none more impressive than the flowering witch-hazels, Hamamelis × intermedia cultivars. One of the most enduring varieties is ‘Arnold Promise’, a mid-sized spreading shrub with narrow upright growth ten to fifteen feet tall; it blooms mid-February here in a warm year. The clear yellow petals create a stunning portrait on bare branches. The display includes a marvelous fragrance, almost too much to take in on a mid-winter day. Today, with more than two hundred witch-hazel varieties to choose from, ‘Arnold Promise’ (introduced by the nearby Arnold Arboretum in Boston) has withstood the test of time. A selection from Belgium named ‘Jelena’ is also deliciously fragrant, producing coppery-orange flowers on horizontal branches.

The individual petals of all witch-hazels have a curious habit of unfolding during the day like party streamers, only to furl again before nightfall. This frost-proof methodology makes for a tremendously long bloom period that can last a month. When planting witch-hazel, choose a bright sunny spot within view of a kitchen window, or along a garden path that you walk each day. Your eyes, nose, and spirit will be enchanted by these elegant shrubs.

A more recent introduction to horticulture and just now finding a home in American gardens is the paperbush, Edgeworthia chrysantha. When planted in free-draining soil and partial shade, it has fragrant blooms that emerge from startling silver buds in late winter. A beautiful specimen greets visitors at the Polly Hill visitor center, and yet another plant resides in Polly’s Playpen. When choosing a spot for the paperbush, be aware that it can grow up to twelve feet tall and wide, and the branches are extremely soft, so avoid planting under roof eaves where snow may fall and crush its delicate framework.

2. Beautiful Bark

Trees with ornamental bark save their best for the winter season, and the Polly Hill Arboretum is home to North America’s most comprehensive collection of stewartia trees, known for their smooth, sinuous, camouflage-colored trunk beneath an exfoliating bark. These summer-blooming small trees are relatives of the tender camellia. However, in contrast they are winter-hardy and thrive on Martha’s Vineyard. An added bonus: White-tailed deer do not favor their stems and twigs. Two impressive mass plantings of both the Japanese stewartia (Stewartia pseudocamellia) and the tall stewartia (Stewartia monadelpha) inspire visitors with their fantastic bark. The Japanese stewartia, which can reach thirty to forty-five feet in height, has mottled bark combining green, silver, and golden hues, and the tall stewartia (twenty-five to thirty-five feet tall) has peeling bark that is cinnamon brown and glows in the early or late-day winter sun.

I would say over the last thirty years the holy grail for beautiful bark trees has been the paperbark maple, Acer griseum. For years this garden aristocrat has been the most sought-after tree for its golden-brown peeling bark. A small tree that tops out at eighteen to twenty-five feet, it is the perfect choice for a Vineyard homeowner with limited garden space. It also offers the added bonus of reddish-orange fall leaf color.

3. Hollies and Berries

When we think about enchanting winter trees, we often think of evergreen hollies. Polly Hill believed the native Vineyard American holly, Ilex opaca, was the perfect windbreak tree for the Island. She particularly liked heavy-fruiting forms of hollies and introduced several into the horticultural trade. ‘Villanova’ is a unique yellow-fruited form of American holly, while ‘Pernella’ is an unusual hybrid discovered by Polly – it has spiny leaves and incredibly large red berries that look beautiful contrasted against newly fallen snow. Another rare but worthy holly is the long-stalk holly, Ilex pedunculosa. This elegant, small (up to thirty feet) tree has elliptical spineless evergreen foliage with fruit that differs from other hollies, not appearing in clusters, but rather as single fruits on a long stalk. The effect is beautiful, and the tree is worth spending the extra effort to find.

Polly Hill also was interested in deciduous hollies, Ilex verticillata (American winterberry) and its cultivars. These large shrubs grow from six to ten feet tall and produce clusters of fruit on bare branches. She found ample inspiration for this group in the swamps and streams of the Vineyard, where the plant thrives in moist soil conditions. Polly named several plants that she selected from wild populations, but despite her own Island introductions, she once confessed to me that the best of the best is called ‘Winter Red’ – year after year it produces a spectacular fruit display. Cronig’s Market in West Tisbury has planted its parking islands with these heavy-berried shrubs, aglow from Thanksgiving to mid-February. Birds eventually discover and eat the fruits, a winter bounty for them.

A mass planting of yellow-fruited ‘Winter Gold’, a related variety, brings welcome color in my home garden. The cut branches of deciduous hollies make a great centerpiece arrangement on our Thanksgiving table. The display lasts as a dried arrangement and combines well with cut winter stems of ornamental grasses. With evergreen or deciduous hollies
it is essential that you procure both female and male plants. The flowers in this group appear on separate plants; that is, a female selection must be accompanied by at least one male
pollinator to enable fruit production.

4. Evergreens, Beyond the Pale

I can safely say that if I never see another planting of the weak-wooded, disease-prone Leyland cypress (×Cupressocyparis leylandii), I will die a happy plantsman. If I had to choose a fast-growing large evergreen for a wind screen or for ornament, I would choose Polly Hill’s all-time favorite, the Yoshino Japanese cedar, Cryptomeria japonica ‘Yoshino’. Several specimens of this original US National Arboretum introduction can be viewed at the Island’s arboretum. Deer-resistant, with bright green to bluish summer foliage, Yoshino takes on a bronze winter cast in open, windy exposures. The tree grows quickly in partial shade or full sun and maintains a uniform pyramidal habit, with a mature height of forty to fifty feet.

A conifer tree of western mountain ranges in the US, the white fir, Abies concolor, is a superior choice for winter garden color. Conical with stunning blue foliage and reaching thirty-five to fifty feet in height here on the Island, the white fir has grown well at the arboretum for many years, yet remains underutilized in modern landscapes. Another western conifer that exhibits phenomenal growth (as high as forty to seventy feet and up to twenty-five feet wide) with the added bonus of being deer-resistant is the western red cedar, Thuja plicata. A recent hybrid called ‘Green Giant’ (twenty-five to fifty feet tall and up to twenty feet wide) is a marvelous specimen plant or a beautiful hedge. Its popularity in recent years has made it readily available at Island nurseries.

While it’s important to know about all of these wonderful plants for winter color, it’s critical that we do not neglect that which is common but underappreciated: the native red cedar, Juniperus virginiana. This tree, a beautiful evergreen whose habit and character speak to the Island’s uniqueness and add picturesque beauty to our farm fields and open spaces, is smaller than the others mentioned, reaching twenty to forty feet. I encourage its use as a specimen plant or windscreen. Its beautiful dark-blue fruits are a favored food source for many bird species.

5. Waves of Amber Grasses

Perennial ornamental grasses can play a vital role in adding color, movement, and sound to our winter gardens. One such grass is the ‘Karl Foerster’ feather grass, Calamagrostis × acutifolia. This narrow upright grass is seed sterile, and when planted in masses creates a river of tawny towers lasting well into February.

Two iconic native grasses on the Island are my favorites: little bluestem, Schizachyrium scoparium, and switchgrass, Panicum virgatum. Little bluestem is a mound of emerald green foliage in the summer but turns amber orange in the fall, and its dry seed heads shimmer in the light well into the winter months. Switchgrass is a much larger grass that can grow up to four feet high or more. It produces airy flower panicles in the summer that form soft seed heads in the winter.

Design Ideas

Create winter landscape vignettes by combining and contrasting foliage colors and textures with tree bark, fruit colors, and mass plantings of ornamental grasses where appropriate. The beautiful evergreen foliage of western arborvitae creates a wonderful contrast to the spectacular yellow fruits of the ‘Winter Gold’ holly. ‘Winter Red’ holly pairs wonderfully with a backdrop of the white fir, a contrast of deep red fruits with glaucous evergreen foliage. Ornamental grasses combine with both deciduous and evergreen hollies. One note of caution: Snow, rain, and wind diminish the effectiveness of grasses by February most winters.

The Polly Hill Arboretum offers free walking tours during the winter months, when you can gather more ideas about appropriate plants for winter landscapes. By choosing the right plants and with thoughtful planning, your winter landscape can be a source of quiet beauty and inspiration.

An Ornamental Grass to Avoid

There is no doubt that ornamental grasses add great drama to the garden. However, in more recent years, one species has dramatically spread into natural areas on Martha’s Vineyard. Silver grass, Miscanthus sinensis, has jumped the garden fence and increased its presence in our rare sandplain habitat. I recommend plants that do not have invasive characteristics. The Massachusetts prohibited plant list, which can be found at plantlist.htm, is a great starting point for invasive species to avoid, but silver grass does not appear on it yet. The Polly Hill Arboretum has found that silver grass is a problematic plant that will likely be banned for sale at some point in the future. There are numerous ornamental grasses that do not invade natural areas that are terrific options for gardeners; be sure to share with garden center staff your concerns about invasives when purchasing unfamiliar plants.