winter interest

Plant Spotlight: Smooth Sumac and Staghorn Sumac

What It Is

Sumacs are plants from the genus Rhus that grow around the world, with over a dozen true sumac species in North America. Despite the name, poison sumac is included with species including poison oak and poison ivy in the Toxicodendron genus. Sumac’s dried, ground fruit is a common spice in Mediterranean and Middle Eastern cooking, and the dried berries can also be used to made a lemonade-like beverage.

There is significant variety in size and form in the genus, but Rhus glabra, smooth sumac, and Rhus typhina, staghorn sumac, are two of the larger forms that can be grown as small trees. Though they are nearly identical in appearance and growing conditions, Rhus glabra is native across North America, including the Spokane region, while Rhus typhina is native only to the eastern half of the continent. Both grow naturally as large, multi-stemmed shrubs forming large colonies, but a bit of yearly pruning will keep them trained into a tree form.

Rhus typhina's rust-colored seedheads persist through the winter for a striking visual display.

Rhus typhina's rust-colored seedheads persist through the winter for a striking visual display.

Why to Grow It

Smooth sumac and staghorn sumac are fantastic plants for four-season interest. In a garden setting, sumac’s bare lower trunks offer architectural interest in spring and summer, while its feathery compound leaves create a dense screen of green foliage. Fall and winter are its real time to shine, though. Large conical seedheads mature throughout the summer, arriving at a deep rust color by autumn.The contrast with the green foliage is stupendous, but even better is the brilliant orange-red fall color. Sumac is one of the first plants to change, making it easy to identify along roadsides and in its native habitat. After the leaves drop, the seedheads persist through the winter, offering a bright spot of color as well as important food for wildlife.

Where to Put It

Sumac is an excellent plant for naturalizing marginal areas, as it does well in extremely poor soils and is very drought tolerant. It can often be seen on steep hills or along the roadside, as it is also resistant to erosion and pollution. In a residential landscape, a single-trunked tree will grow to about 15’ high with a slightly wider spread. Sumac will take some shade, but prefers full sun, and has low water requirements. Because the foliage is massed towards the top of the plant, sumac can be complemented with low- to medium-height perennials and shrubs around it to provide a visual balance.

Plant Spotlight: Corkscrew Willow

Corkscrew willow is an excellent choice for containers, because it tolerates heavy pruning

Corkscrew willow is an excellent choice for containers, because it tolerates heavy pruning

What It Is

Corkscrew or curly willow is a cultivar of the Chinese willow species Salix matsudana.  Left to its own devices, corkscrew willow will grow into a small tree from 20’ to 30’ high, but it can be heavily pruned and maintained as a smaller shrub without harming the plant.

Why to Grow It

As its name suggests, corkscrew willow has twisted, curly branches and similarly curly leaves. The stems are an attractive feature in the garden or when cut and used in floral arrangements. It’s a quick-growing plant that tolerates a wide range of conditions, so it can be a good solution for trouble spots. While its curly branches are a fantastic winter feature, corkscrew willow’s interesting foliage makes a statement as well, especially in autumn when the leaves turn yellow.

Where to Put It

While corkscrew willow is a fast-growing tree, it is also a short-lived one, with a lifespan of just a couple decades. In many landscapes, it is a better choice to maintain it as a large, multi-stemmed shrub. Like most willows, corkscrew willow responds well to coppicing, where the plant is cut down to the ground to stimulate the growth of vigorous new shoots. This makes it easy to control the size of the plant and provides an opportunity to harvest the stems for decorative use. Because corkscrew willow tolerates pruning so well, it is an excellent choice to grow in large pots or containers where it might be necessary to control the size. In the ground, corkscrew willow’s shallow root systems have been known to lift nearby paving, so care should be taken in locating it. While it will thrive in moist soil with full sun, corkscrew willow will tolerate a wide range of exposure and soil conditions, with the caveat that it does not do well in drought.

Plant Spotlight: Symphoricarpos Species

What It Is

Symphoricarpos is a genus of shrubs commonly known as snowberry or coralberry, depending on the color of the fruit. It is native throughout North America, with the species Symphoricarpos albus common throughout the Inland Northwest. Our native snowberry is easily recognizable in the autumn and winter for its dense clusters of white berries, which persist months after the leaves fall. Its delicate foliage and small pink flowers are attractive but inconspicuous. All varieties are fairly small shrubs, generally topping out at five feet high and wide.

This hybrid coralberry holds its bright berries well into winter.

This hybrid coralberry holds its bright berries well into winter.

Why to Grow It

As the name suggests, snowberry and coralberry are prized for their prominent berries. A variety of cultivars and hybrids have been bred by the floral industry for a spectrum of pink berry colors and longevity in cut arrangements. You can enjoy those improvements just as easily in your garden, where the berries can also provide a winter food source for songbirds. Snowberry is also an excellent plant for naturalizing areas and erosion control, as it slowly spreads to form thickets when left to its own devices. Regularly harvesting its berry-covered stems, however, is enough to keep it in check.

Where to Put It

Symphoricarpos should be planted in full sun to part shade. Native Symphoricarpos albus is quite drought-tolerant, but nursery cultivars do best with supplemental water in the summers. Snowberry is fairly unremarkable most of the year, so place it with other plants that will offer more dynamic interest through the spring and summer, then let it take center stage in the winter. If you plan to use the berries in flower arrangements, consider locating snowberry off a covered porch or other area where it can be easily accessed when snow begins to pile up.

Plant Spotlight: Ilex x meserveae

What It Is

Commonly called blue holly, Ilex x meserveae is a group of hybrid hollies originally bred by Kathleen Meserve of New York after World War II to feature showy foliage and berries while maintaining cold-hardiness for Northeast winters. Size varies depending on variety, but generally ranges between 6’-12’ high and wide.

Why to Grow It

When most of the landscape is dull and dormant in the winter, Ilex x meserveae puts on a show with its glossy leaves and clusters of red berries. The berries provide winter food for birds, adding to the interest.

Where to Put It

Ilex x meserveae needs full sun to part shade to thrive. It will mature to a large shrub, so take advantage of its evergreen foliage and showy berries to screen a boring wall or fence. It also works well as an evergreen hedge. Ilex x meserveae requires a medium amount of water and will need artificial irrigation in the Spokane/Coeur D’Alene climate during the summer.

Like all hollies, a male and female plant are each necessary for the female plant to produce berries. One male plant can pollinate several female plants, but it’s important to ensure that the varieties flower at the same time. Most cultivars, however, come with a male and female form that have been bred so that their bloom times align. The Berri-Magic line even includes a male and female plant in each container to ensure berry production.

Glossy evergreen leaves and red berries make this holly a winter showpiece.

Glossy evergreen leaves and red berries make this holly a winter showpiece.