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Winter Gardening: Native Shrubs and Trees for Winter Interest

By Kate Brittenham

Though the ground may be frozen (and if you are lucky, covered with a picturesque blanket of snow), there can still be interest in our gardens, both for us and for wildlife. We have compiled a sample list of native shrubs and trees that should be recognized for their beauty even in the dead of winter. There are so many more, but we had to limit ourselves!

BetulaBetula papyrifera (Paperbark Birch)

I'd like to go by climbing a birch tree,
And climb black branches up a snow-white trunk
Toward heaven, till the tree could bear no more,
But dipped its top and set me down again.
That would be good both going and coming back.
One could do worse than be a swinger of birches.

Excerpt from Birches by Robert Frost

Betula papyrifera

Growing up, Betula papyrifera (Paperbark Birch) was one of my absolute favorite trees, because it created the best props for an uninhibited imagination. The peeling bark became the paper for my secret messages or ancient treasure maps. It was bracelets and necklaces or dinner plates. The options were limitless! I remember one children’s book in particular that I grew up with—The Rough-Faced Girl—an Algonquin take on the Cinderella story, where the heroin actually makes a dress out of birchbark.

As an adult, I still have a great appreciation for the beautiful bark of this tree. Incredibly easy to identify due to its peeling, papery bark, Betula papyrifera enhances the winter landscape. Use it as an accent tree or in a mass, it will stand out regardless. An allee of these trees easily creates a winter wonderland. Place it against a backdrop of evergreens, or pair it with shrubs like Ilex verticillata or Swida sericea that will pop against the pearly white bark.

Rhus typhina (Staghorn Sumac)

Rhus typhina A very underrated shrub and frequently dismissed as a landscape plant, probably due to its “weedy” character and atypical appearance, Rhus typhina might not look like your typical garden plant, but the shrub provides valuable habitat for songbirds, who feed on its seedheads. It is named for the small hairs that grow along the younger branches, creating a fuzzy texture, not unlike the “velvet” on the horns of a stag.

Rhus typhina

Rhus typhina along a roadway in Bennington, Vermont.

It is listed here for the unique red conical fruit, which stands out in stark contrast in the wintery landscape. Throughout the season, Rhus typhina is foliated by large, long, and pinnately shaped leaves, which turn to a nice red in the fall, but drop with the temperature. What is left through the winter season are the fruits, which make for great dried and fresh arrangements.

Largest of the North American sumacs, Rhus typhina typically grows 15-20’ in height. It will spread and form stands, making it an excellent choice to create groves or thickets in the landscape.

 

Hydrangea quercifolia (Oakleaf Hydrangea)

Oakleaf HydrangeaI will begin this section with a disclaimer: I have never been a fan of hydrangeas. I always thought they were too 1960s suburbia, until I began working with plants and it was this particular species, the Oak Leaf Hydrangea, that first brought me around. The moment I truly recognized their beauty was during a trip to the New York Botanical Garden in early spring, when very little was awake. The bark of Hydrangea quercifolia was absolutely striking at this point in the season and I was forever after a convert.

Hydrangea quercifoliaHydrangea quercifolia is an absolutely fantastic landscape plant that has really gained in popularity in recent years, due to its versatility and seasonal interest: a great filler shrub, spreading up to 6-8ft in width and height, it is drought tolerant once established, and performs in part shade as well as full sun. Low maintenance and deer resistant, Hydrangea quercifolia produces lovely late season blooms, and the characteristic oak-shaped leaves change to a lovely red or deep purple in the autumn, as shown above.

In the early winter, the blooms will remain dried on the stalks, and make for excellent additions to a dried flower arrangement. The pale brown and beige bark provides interest throughout the winter, peeling in layers similar to Betula papyrifera, and is truly beautiful against the snow. There are many cultivars and ‘Snow Queen’ in particular is a great option for even more distinct bark coloration and peeling. Pictured above is the straight species.

Swida sericea (Red Osier or Red-Twig Dogwood)

SwidaThis is a plant meant for the winter landscape. A thicket-forming shrub, it creates horizons of red wherever it grows and does well in a variety of conditions. I have seen it happily established along the slopes of medians on I-87 in upstate New York, but it is happiest in moist to wet soils, like marshes and wetlands. An erosion stabilizer, it is also a great rain garden plant. Best grown in masses, and pairs well with grasses and perennials with grass-like foliage, like Amsonia hubrichtii and tabernaemontana—particularly in the fall and winter. It also pairs well with evergreens like Ilex opaca for a bit of that holiday color.

A host for the larvae of the Spring Azure (Celastrina ladon) butterfly, in the late spring, the small flowers attract pollinators and later, turn to berries that the birds love. The berries have high nutritional value and ripen just around the time that the birds migrate. Still not convinced of its landscaping value? For those of you who live in deer-inundated areas, Swida sericea is deer resistant—although not deer proof (very few plants truly are).

Swida sericea

A little bit of fun history: the twigs have historically been used in baskets, which I can imagine would be beautiful with that red color, assuming it lasts. (As the plants age, older twigs become brown; judicious pruning renews red stems.) The common name “osier” comes from the name given to willow twigs that were used to create baskets.

Ilex verticillata (Winterberry)

Ilex verticillataWithout fail, the top plant for winter interest, in my opinion, is Ilex verticillata. When anyone asks me for winter interest, this beautiful plant immediately comes to mind. For most of the growing season, it is a relatively understated background shrub, with a nice shape and lovely foliage, but nothing striking. Its true landscape purpose emerges in late fall and early winter, when the leaves fall and the bright red berries (a favorite of songbirds) become visible. Commonly used in holiday decorations and arrangements, popular among floral designers, Ilex verticillata is a requisite for the winter garden.

Ilex verticillataIn the wild, Ilex verticillata can grow quite tall, to about the height of a small tree, however there are many dwarf varieties available on the market. One lovely (and easy to find) dwarf cultivar is ‘Red Sprite’. It is important to note that, like all hollies, Ilex verticillata is dioecious, meaning that the flowers on one shrub will be all female, and all male on another. In other words, in order to get those beautiful berries, both male and female shrubs are necessary. A good male cultivar that will pollinate happily ‘Red Sprite’ is the ‘Southern Gentleman’ cultivar. For larger sized shrubs, both ‘Winter Red’ and ‘Jolly Red’ produce bountiful berry-laden branches.

Ilex opaca (American Holly)

Ilex opacaI have heard that many people hold the opinion that the American Holly is not as nice as the English, but I personally do not understand that perception. I think to the untrained eye, they are nearly indistinguishable, and Ilex opaca provides a marvelous substitute for the English. Its classic spikes, green color and vibrant berries evoke the spirit of the winter season. It is also deer resistant—you would have to be incredible hungry to tangle with those spiky leaves.

Ilex opaca is considered a shrub, but will grow quite tall and in a pyramidal shape. It can be trained to stay low but there are also cultivars such as ‘Maryland Dwarf’ and ‘Clarendon Spreading’ that are natural dwarves. Ilex opaca can also be pruned into a hedge-shape. Again, as an Ilex, the American Holly requires both male and female plants in order to produce berries. Put it in full sun or part shade, it will happily grow in either condition.

Ilex opaca


Favorite Fall Plants

By Kate Brittenham

As the leaves slowly start to turn, we are reminded that despite the warm weather we’ve been having in New York, it is in fact the end of summer, and autumn is right around the corner. If you are like me, you are bewildered by this realization, wondering where the summer went! This season, as opposed to others, particularly felt very quick to me.

But now I can feel the pace slowing, and since Starbucks has officially put pumpkin spice latte back on the menu, autumn feels inevitable. Fortunately, autumn in the Northeast is typically spectacular—infamously so. For those of us who live here, fall is a special treat, and one I always look forward to, so in honor of the changing seasons, we thought we’d profile some of our absolute favorites for autumn interest, that you could incorporate into your gardens and landscape to get some of that spectacular color.

Solidago - Goldenrod

Solidago (Goldenrod)

I love Goldenrod too much to pick just one species to talk about. Goldenrod has gotten a bad reputation, being confused frequently with ragweed, which causes hayfever, however Goldenrod is not wind pollinated, and therefore does not cause allergies. A very drought-tolerant plant, that iconic golden color always brings back memories of my childhood roaming the former dairy pastures of upstate New York. You can hardly go wrong with any species, and all of them are fantastic pollinator plants.

Some even do well in shade, like Solidago flexuosa, the Zigzag goldenrod, and S. caesia, the Blue-stemmed or Wreath goldenrod. They will also do well in full sun, given adequate moisture. Some, such as Solidago bicolor, silverrod, the white species, are great for dry areas.  It has a lovely, candle-like single stem.  Solidago nemoralis (Gray goldenrod), is one of the smaller species, and does well in very tough sites with poor, rocky or sandy soils.  There is even a goldenrod for places that get hit by salt frequently (such as road salt in the winter), like Solidago sempervirens (Seaside goldenrod), which grows in the wild in coastal locations.

I think any meadow should be sure to include Goldenrod for that fantastic autumn color and pollinator value. Some of the best individual species for the meadow are Solidago speciosa (Showy goldenrod),  S. canadensis (Canadian goldenrod), S. rugosa (Rough goldenrod), S. odora (Aromatic goldenrod), and S. rigida (Stiff goldenrod). Some species can be aggressive—Solidago canadensis and S. rugosa, for example, but when planted with similarly aggressive plants (like some grasses and other Solidago species), they can be kept in check with regular mowing.

Goldenrod species


Parthenocissus quinquefolia (Virginia Creeper)

Parthenocissus quinquefolia (Virginia Creeper)

Parthenocissus quinquefolius gets a bad rap for strangling trees—I am not entirely certain where this has come from, but it may be influenced by the invasion of vines like Asian Bittersweet, which do wreak havoc on our forests. Parthenocissus does not behave like Bittersweet—while it may be found climbing up trunks and branches, it does not harm those trees. So feel fine planting this fall stunner in your backyard, on your fire escape—just about anywhere. Parthenocissus is an incredibly adaptable plant and has a wide variety of fall color from brilliant fire red (shown above on arbor), or a deep purple that complements the blue berries birds love (shown below). Plant Parthenocissus on a wall, fence, arbor or exposed stones for a brilliant autumnal display.


Eragrostis spectabilis (Purple Lovegrass)

Eragrostis spectabilis (Purple Lovegrass)

Eragrostis spectabilis is a very surprising grass. For the majority of the season, it is not much to look at, then suddenly, around late summer, it releases its seedheads producing this stunning purple cloud through the fall. It is a low, mounding grass that will not get very high—subsequently, I find that it makes great borders. It also does well designed as swaths of color placed in the distance, mixed in with other perennials and grasses in landscapes.  It is especially useful as a meadow plant, if the desired meadow height is below 2 feet in height or as an edging for taller meadows.

Eragrostis

Above, Eragrostis paired with other grasses in a border surrounding a stepping stone path (currently obscured from view) at Flying Trillium Gardens and Preserve. Some asters and goldenrod can be seen in the background.

Very drought tolerant, it prefers well-drained soils, but will do well in a formal garden setting. Below, a border of Eragrostis frames a perennial border in a suburban front yard in upstate New York, just outside Albany, NY.

Eragrostis in a perennial border


Schizachyrium scoparium (Little Bluestem)

Schizachyrium scoparium (Little Bluestem)

Another unique fall interest plant, and an all around favorite of mine, is Schizachyrium scoparium, or Little Bluestem. A fantastic species, Schizachyrium does prefer well-drained, drier soils, but is very adaptable, so long as it has adequate drainage. As opposed to Andropogon gerardii (Big Bluestem), Schizachyrium will not get very tall. And with so many cultivars to choose from, the color possibilities are pretty much unlimited. Some of the more exciting cultivars include S. scoparium ‘The Blues’, S. scoparium ‘Standing Ovation’, S. scoparium ‘Prairie Munchkin’ (a dwarf variety), S. scoparium ‘Carousel’, and S. scoparium ‘Smoke Signals.’

It should be said, however, that the straight species itself has so much variation that cultivars are almost unnecessary. I have driven past multiple stands on the Taconic Parkway in New York State, where one population might have a slight bluish hue and then 5 miles down the road there is another more purple population and then 5 miles past that there yet another more red population!

Schizachyrium scoparium stand


And for the finale: Acer saccharum, or the Sugar Maple:

Acer saccharum - Sugar Maple

Nothing is more iconic about the Northeast as the fall, and nothing contributes more to that than Acer saccharum. It lights up the forest, heralding the arrival of winter and the promise of maple syrup to be tapped, only a few months later. While not the only tree that can be tapped, it has a high sugar content, making it the most popular species for that purpose. And of course, nothing beats this tree for fall color. A great specimen tree as an individual, the color also looks great in a mass.

A true New England-like scene, shot in Hamilton, NY.

A true New England-like scene, shot in Hamilton, NY.


Purple Pollinator Power: Cercis Canadensis, The Eastern Redbud

by Kate Brittenham

I suffer from DWB these days—Driving While Botanizing. How many of you can relate? I am positive it is endemic amongst plant lovers. The things that catch my eye this time of year are most definitely the early blooming trees. Most of these bloom in shades of white and pink, but there is one that stands out from the crowd: the eastern redbud. And this week in particular seems to be peak season in the lower Hudson Valley.

A subtle but stunning tree, the redbud, or Cercis canadensis, will not reach great heights. An understory tree, its purple-pink flowers make it a statement in the landscape, and it has been wholeheartedly embraced by the nursery and horticulture industry for its ornamental umph. Its short stature makes it an excellent street tree and you will easily spot it this time of year in many plantings alongside public roadways. While there is a non-native redbud, Cercis chinensis, it is very easy to distinguish from the indigenous variety; Cercis canadensis is a tree, and has a single trunk, while Cercis chinensis is a shrub and has multiple branching stems.

The Lady Bird Johnson Wildflower Center states that there are three varieties of Cercis canadensis: Cercis canadensis var. canadensis, Cercis canadensis var. texensis and Cercis canadensis var. Mexicana—something I was unaware of until doing my research. The latter is found in Mexico and parts of western Texas; C. canadensis var. texensis is indigenous to the geographic region found between Texas, south of Oklahoma, and northern Mexico; and the variety canadensis is indigenous to our region, though its range extends all the way down to Texas as well.

Cercis canadensis in flower. Taken at the New York Botanical Garden. Photo: Kate Brittenham


Cercis canadensis in flower. Taken at the New York Botanical Garden.
Photo: Kate Brittenham

It is a member of the Fabaceae (Pea) family, which is made abundantly clear by looking at the flowers, which resemble many of those in its family. Up close, Cercis canadensis’ flowers can look like alien growths growing on tree bark. The flowers can form directly off of the bark, not off any long stems or branches, thus giving it this “fungal, growth-like” appearance. In the summer, it produces beautiful, waxy heart-shaped leaves. Besides its seasonal interest, Cercis canadensis is a great plant for both sunlight and shade, proving itself adaptable to both light conditions.

Cercis canadensis in a shaded woodland, with a pollinator friend. Photo: Carolyn Summers.


Cercis canadensis in a shaded woodland, with a pollinator friend.
Photo: Carolyn Summers.

Additionally, Cercis canadensis is a fantastic pollinator. Typically blooming from March until May, Cercis canadensis is one of those important early pollinator plants. According to the Xerces Society, it holds particular value to native long-tongued bees who are attracted to its nectar and pollen. The tree also plays host to butterfly caterpillars and other insect larvae who munch on its leaves.

A fantastic substitute for non-native cherry trees—for which it is often mistaken—Cercis canadensis is truly an impressive tree in the landscape, a real show-stopper in the early spring in any garden. But more importantly, it provides an important ecological service for our pollinators.

Resources:

Pollinator Plants: Mid-Atlantic Region. Xerces Society. July 2015. <http://www.xerces.org/wp-content/uploads/2014/09/MidAtlanticPlantList_web.pdf>

“Redbud. Cercis canadensis. Senna family (Caesalpiniaceae).” Illinoiswildflowers.com. <http://www.illinoiswildflowers.info/trees/plants/redbud.htm>

“Cercis canadensis.” December 2015. Lady Bird Johnson Wildflower Center. <http://www.wildflower.org/plants/result.php?id_plant=ceca4>


Cardamine diphylla (Toothwort)

By Kate Brittenham

When we first began putting together this list of pollinator-friendly plants, we wanted to include species that are less well known, and could use a moment in the spotlight. Cardamine diphylla (Toothwort) is one such plant. Native to Northeastern woodlands, it blooms from March to June, a sweet, delicate bell-like white flower which attracts early pollinators such as long-tongued bees and flies. This plant itself typically doesn’t get much higher than 16”, but it has a clonal characteristic, forming colonies.

Toothwort: Photos courtesy of Carolyn Summers.

Photos courtesy of Carolyn Summers.

In addition to providing early season nectar, Cardamine plays host to Pieris virginiensis (West Virginia White), a butterfly commonly mistaken for the common cabbage white, which lays its eggs on the plant’s leaves.  The invasive plant garlic mustard will sometimes fool the butterfly into laying eggs on its leaves instead, as both plants are members of the Mustard Family.  But although distantly related, the caterpillars of the West Virginia White cannot digest the leaves of garlic mustard, and perish.  The proliferation of invasive garlic mustard may be one reason the West Virginia White is becoming scarce.  Perhaps planting its host plants, like Cardamine and other native mustards, will encourage its survival.

There appears to be a common misconception that if a plant is not found in bright, sunny meadows, it is not a pollinator plant. Cardamine is just one plant that demonstrates how untrue that is. We chose Cardamine, not only to bring attention to a plant that is not commonly associated with pollinators, but also to show that even if you have a shady, wooded area, you can still provide habitat for pollinators.

Pieris virginiensis. Photo courtesy of Wikimedia Commons.

Pieris virginiensis. Photo courtesy of Wikimedia Commons.

Remember, pollinators have been here for many, many, years developing plant relationships. It should come as no surprise that they have not limited themselves solely to the open, sunny meadows. So if you have a shade garden, rest assured that you can incorporate pollinator-friendly plants such as Cardamine diphylla. While not a common plant at nurseries, there are some that do provide it for sale, such as Edge of the Woods Nursery in PA. Consider doing a quick search with local nurseries—some of them may never have heard of it, but consumer demand is a powerful thing. If more nurseries hear that people desire plants they do not stock, they may become interested in carrying those species.

Photos courtesy of Carolyn Summers.