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Helleborus niger starts blooming in early winter and continues through the season. It’s just one of the many plants that extend the season in the landscape. All photos by Doug Oster

Gardening Green with Doug 

How to Add Color and Interest to Your Winter Garden

By Doug Oster

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December 2, 2020

The expansive outdoor sales area at one of my favorite garden centers has been transformed into a Christmas tree lot, like most other garden centers.

I’m on the hunt for bargains though and know there are two heptacodium shrubs left. As part of my frugality, keeping an eye on what’s still around as the season wanes usually pays off. It’s better for everyone concerned when the plant gets a good home before the ground freezes solid.

I found the heptacodium in the back of the nursery, their roots covered in a blanket of mulch meant to protect them all winter. They will be much happier planted in the ground.

Also known as seven-son flower, heptacodium is a large shrub — and an underused plant in the landscape, in my opinion. The sun lover is indestructible and will also be happy in partial shade. It has late-blooming, white flowers that fade to deep pink, but that’s not why I’m planting these two (or the other three I put in place seasons ago). It’s the tan exfoliating bark that makes them one of the stars of the winter garden.

As the planting season winds down, there’s still time to sneak shrubs and trees in the garden. It's also a great time to add plants with winter interest to the garden.

But even if they don’t get planted, look around and see these plants that will help continue the beauty in the garden year-round.

It’s all about the bark

Aside from heptacodium, there is a wide range of plants that have spectacular bark.

The Chinese lacebark elm is an unusual and uncommon tree. I first saw one on the campus of Chatham University, which is also an arboretum. Chinese lacebark elm is a fast grower that can eventually reach 50-feet, donning stunning multi-colored bark. It has good resistance to Dutch elm disease and is also resistant to Japanese beetles and elm leaf beetles.

There are many other wonderful trees and shrubs at Chatham; it’s one of Pittsburgh’s hidden gardening treasures.

The shagbark hickory is a big tree with rich, fall color, that produces nuts as a bonus. Off-season though, the thick, layered bark is a show stopper.

I longed for a paperbark maple for years and finally planted one about a decade ago. When I walk by it, I sing a version of the Beatles' song “Paperback Writer,” substituting the name of the tree in the chorus. It’s a slow grower, like many maples, and has cinnamon-colored, flaky bark.

Stewartia is another underused tree offering four seasons of interest. It has a beautiful, natural shape, pretty white peony-like flowers in summer, nice fall color. Its flaky bark reveals shades of gray, cream and tan.

Winter shrubs to give landscape color

If you want to see what a mass of winterberry holly looks like, drive past Phipps Conservatory and Botanical Gardens. You'll view a sea of bright red berries. In the wild, this native shrub loves moist, acidic soil, but it is adaptable to a wide range of growing conditions. Winterberry prefers full sun, but the deciduous plant will put on berries in partial sun too. ‘Berry Heavy’ is a great cultivar. ‘Berry Heavy Gold’ produces unique gold-colored berries. ‘Berry Poppins’ only reaches about 4-feet tall and 4-feet wide for gardeners who don’t have room for full-sized cultivars that can grow up to twice that size. All are available from Proven Winners ColorChoice Shrubs and some are sold at local nurseries.

Witch hazel is also a native shrub that flowers in early-to-late winter, depending on the variety and weather. Some cultivars have pretty yellow flowers, while others are red. There is something amazing about seeing a plant in full bloom during the cold.

Red twig dogwoods should not be confused with dogwood trees. Red twig dogwoods (Cornus stolonifera) are multi-stemmed shrubs with either bright red or yellow stems that make a perfect presentation against winter white snow. The shrub is easy to grow in partial-to-full sun and has many cultivars to choose from — even some with variegated foliage for spring and summer interest. ‘Arctic Fire’ is a favorite from Proven Winners ColorChoice Shrubs and is available at local nurseries.

I love oak leaf hydrangeas. It's another plant with many different seasons of interest. Conical white flowers fade to pink and the big “oak leaves” turn deep red in the fall. When the foliage finally drops, it reveals a deep orange, brown peeling bark that is attractive against the snow.

Perennials to plant for a winter show

Of all the perennials growing in my landscape, Helleborus niger is the star that begins blooming now and continues through the winter. During a January thaw, the honeybees will visit looking for something to eat. The buds start with a pinkish hue and open to pure white, often fading back to pink. The evergreen foliage is a great plus, too. Choose carefully when planting a hellebore; it loves part shade and resents being moved, often waiting a few years to bloom again.

These plants are available right now at nurseries, sold as holiday plants. I’ve been finding them at local nurseries, sold as indoor holiday plants, which should be a crime against horticulture, as this is a long-lived, outdoor plant. The thought of them being thrown to the curbside after New Year’s drives me crazy. I’ll buy them up and try to overwinter them in an unheated greenhouse, but they could be babied along on the windowsill until spring and then planted in the garden.

There are countless ornamental grasses that, when left standing in the winter, put on quite a show. Regardless of size or shape, they are perfect deer-resistant additions to the landscape and will grow just about anywhere. Even though they love full sun, they will grow and produce plumes in partial shade, too. ‘Morning Light,’ ‘Karl Foerster’ and ‘Pink Hair Grass’ are just a few fun varieties to plant.

If you’re planting season has finished, add these plants to your list of things to grow for next year. For me, I’m not done until the ground freezes solid. Either way, stretching the season with these winter stars will make the garden a special place to be, even in the dead of winter.

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The buds of Helleborus niger begin pink and then open to pure white flowers.
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It’s great to have native species, witch hazel blooming in the winter. This one has beautiful yellow flowers.
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Frosty blooms of red, flowering witch hazel.
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These winterberry shrubs in front of Phipps Conservatory and Botanical Gardens put on quite a show.
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Heptacodium has a wonderful exfoliating tan bark.

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Doug Oster writes a weekly column for The Green Voice Weekly Newsletter. He also the host of The Organic Gardener Radio Show every Sunday morning at 7 a.m. on KDKA radio 1020AM. 

To see more garden stories, photos and videos go to dougoster.com.