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Viburnums For Any Landscape

Right: bright red Viburnum opulus berries, do droop. They also feed hungry songbirds.

What exactly is a Viburnum? Viburnums are trees or shrubs, evergreen or deciduous, that may be diminutive three-foot globes or grow 60 feet tall. Their leaf texture varies from smoothly shiny to velvety, and, their leaf edges may be serrated, dentate, lobed, or not! Viburnum flowers are either round or flattish and range in color from white to pink. The blossoms are either deliciously fragrant, have absolutely no scent, or can be downright offensive. Just forget trying to determine what viburnum you are admiring by its fruit color alone since berries range from yellow to orange, red to black, and blue to purple.

According to the great Georgia plantsman, Dr. Michael Dirr, their characteristics are simply too varied to make a definitive identification without a very good reference guide. In his 2007 guidebook, Viburnums, Flowering Shrubs for Every Season, by Timber Press, Dirr admits that even taxonomists can’t agree on how many species presently exist in the genus Viburnum with the true number probably falling somewhere between 160 to 250.

What makes a Viburnum a Viburnum?

V. Carlesii - Photo by Pam Beck
The Koreanspice bush, V. carlesii, provides a perfect example of a viburnum’s opposite leave arrangement.

Famed tree and shrub specialist Michael Dirr’s definition is:

  1. The fruit is a drupe, generally ellipsoidal, flattened, ovoid to rounded, with a fleshy coat, hard bony endocarp, and a single seed within; and
  2. The leaves are always arranged opposite; a few species, occasionally, have three leaves at a node.

Growing Viburnum

Viburnum diltatum (Image by KENPEI)

Besides their exquisite beauty, the main reason why we embrace viburnums in our home landscapes is their extreme hardiness. Many varieties can be very drought tolerant (once established) as some of our best Southeastern native viburnum hail from dry woodlands. A few, such as our native Arrowwood, will also tolerate wet feet. Most will grow well in full sun to part shade, can take a variety of soil types, and still thrive.

Planting Viburnum

In the absence of good soil, you could amend the planting hole fill dirt with Black Gold Garden Soil for improved drainage that will still provide enough moisture retention essential for a newly transplanted viburnum. Otherwise, mulch the base of your new addition with Black Gold’s Garden Compost Blend in order to help hold moisture, keep developing roots cool in summer and warmer in winter, and to suppress weeds.

Great Viburnum

In my home landscape, I have found several species of viburnum grow well under the canopy of a large Black Walnut tree, where it is very dry. Here I have planted Koreanspice bush (V. carlesii) and Cranberry viburnum (V. opulus), and they both perform beautifully.

Viburnums have also been evaluated for their resistance to deer grazing. The toughest survivors of deer predation are our native Arrowwood (V. dentatum); Blackhaw (V. prunifolium); Smooth witherod (V. nudum), which is sometimes erroneously called “possum haw” and, the Maple-leaf arrowwood (V. acerfolium).

Koreanspice Viburnum

The flowers of Koreanspice viburnum are so fragrant. (Image by Bouba)

Koreanspice viburnum (V. carlesii, Zones 4-7) is one of our most popular, old-fashioned, pass-along southern shrubs. Grown for its intensely sweet springtime fragrance, the late March to early April flowers of Koreanspice begin pale pink, turning white with age, grow 2-3 inches across, and are rounded. This 8-10 foot tall shrub has dull green leaves that turn reddish in the fall, and red to black fruits.

Cranberry Viburnum

Cranberry viburnum is named for its brilliant cherry-red fruit clusters that begin coloring in late summer. The popular double-flowered variety ‘Roseum’ is sterile and bears no fruit.

The Cranberry viburnum is named for its brilliant cherry-red fruit clusters that begin coloring in late summer. Its famous leaf fall color is much more dramatic in cooler regions where leaves turn gold, red, and burgundy. A very good cultivar is V. opulus ‘Compactum’, which should top out at just 5-6 feet.

Chinese Snowball

For sheer drama, nothing compares to the Chinese Snowball (V. macrocephalum). This multi-trunked small tree can reach 12-feet or more in height and grow just as wide. Sometimes semi-evergreen in mild winters, this very dark-leafed viburnum is beloved for its 6-8 inch, rounded, springtime flowers that begin pale chartreuse and age to purest white. They are so beautiful that we can forgive it for not bearing any scent. A significant bonus is that it also flowers again from late summer into fall. Since the Chinese Snowball’s hydrangea-like flowers are sterile, there is no fruit, therefore no unwanted seedlings.

Bodnant Viburnum

Viburnum x bodnantense ‘Dawn’ is an early bloomer with lovely fragrant pink flowers. (Image by Magnus Manske)

Your winter landscape could be delightful including a Bodnant viburnum in it. Viburnum x bodnantense ‘Dawn’ has bright pink, strongly perfumed flowers in late February to early March in my Wake Forest, North Carolina, Zone 7-8 garden. The small, rounded, sweetly fragrant flowers are borne on bare branches on a rather rangy shrub, but ‘Dawn’ blends nicely into the mixed border the rest of the year.

Viburnum Tinus

Garden centers offer V. tinus ‘Spring Bouquet’ in autumn, which is the right time to plant them. During the late fall months ‘Spring Bouquet’ forms tight rose-colored clusters of buds that will start popping open during the first months of the new year. These viburnum flowers are only slightly fragrant, but they will cover the small shrub. This evergreen viburnum will need part shade in summer, winter protection from sun, plus they benefit from being shielded from desiccating winds.

Doublefile Viburnum

Doublefile viburnum (Viburnum plicatum) has lovely tiered branching and should not be pruned.

Since they bloom in early April, Doublefile viburnums, V. plicatum f. tomentosum, are great substitutes for ailing native dogwoods. Named for its flowering habit of doily-flat flowers positioned side-by-side along the top of long horizontal branches, this is a stunning small tree. These viburnum are deciduous in winter, have dark green foliage in summer, and bright red berries in late fall. A cultivar named ‘Summer Snowflake’ will bloom well in early spring, then sporadically repeat off-and-on throughout the summer.

Chindo Viburnum

Chindo viburnum is another popular viburnum that isn’t grown for its flowers at all. Promoted by the late Dr. J C Raulston of North Carolina State University, V. awabuki ‘Chindo’, is a loosely pyramidal-shaped, shiny-leafed, evergreen shrub that can reach 15-20 feet. It grows in sun or shade and is shaped reminiscent of a large-leafed holly, so it makes an ideal screening plant. One warning is that a Chindo viburnum won’t like winter temperatures that drop below zero; so, if it does get that cold you may have to trim your plant back severely in springtime to encourage new growth to flush.

There is probably a perfect viburnum for just about any location in your landscape, so how do you go about narrowing your selections? Ask your garden center professional for their recommendations, check with your local Cooperative Extension Service, and find a copy of Dirr’s Viburnums book.

 

V. awabuki ‘Chindo’ - Photo by Pam Beck
The ‘Chindo’ viburnum is an outstanding evergreen screening shrub. (Photo by Pam Beck)

What Are Good Shrubs for a Home’s North Side?

Gold-and-flame-leaved Forest Flame reaches 6 to 10 feet and has chains of ivory spring flowers.

“I am having trouble with roses in the constant north side shade area of my home. Looking for a possible flowering shrub or a better suggestion for this area at the front of our house.” Question from Larry of O’Fallon, Missouri

Answer: Roses by default are sun-loving. Just a handful of species roses and cultivated roses will tolerate partial shade. (Click here to read another AGE about shade-tolerant roses.) But, there are loads of flowering shade-tolerant shrubs that will grow beautifully on the north side of a home. Here are some of my favorites. All of them should be hardy where you live in Missouri.

Shade-Loving Shrubs

Reblooming Azaleas (Rhododendron spp.): Encore® and Bloom-A-Thon® Azaleas will rebloom and some are even evergreen. I recommend them if you have slightly acid to acid soils with good drainage.

Smooth Hydrangea varieties (Hydrangea arborescens): Tolerant of sun and shade, smooth hydrangeas are very hardy and native to your region. Some of the new varieties bloom for a long time in summer, and then their flowers remain on the plants and continue to look pretty into fall and winter. I love the many varieties sold by Proven Winners, such as the pink-flowered Invincibelle, among others. (Click here to view them all.)

Yak Rhododendrons (Rhododendron hybrids): There are so many outstanding evergreen Rhododendrons that grow beautifully in shade, and yak forms are extra tidy and compact. ‘Grumpy‘ is an outstanding yellow-and-pink-flowered form that reaches 5 feet at maturity and has dark, evergreen leaves.

Lily of the Valley Shrub (Pieris japonica) is another evergreen that likes growing conditions similar to that of azaleas and rhododendrons. Interstella has pink chains of blooms in spring and only reaches 4 feet at maturity. Larger varieties include the outstanding gold-and-flame-leaved Forest Flame, which reaches 6 to 10 feet and has chains of ivory spring flowers. It’s a real showstopper.

Hartlage Wine sweetshrub (Calycanthus x raulstonii ‘Hartlage Wine’) grows well in partial sun to light shade and has very fragrant maroon-red flowers in late spring. At maturity, it reaches 6 to 8 feet, so give this one some space. In autumn, its leaves turn yellow and orange before falling.

We have an excellent article, by horticulturist Russell Stafford, that details how to properly plant new shrubs in the landscape. Please click here to view it. I hope that some of these shrubs interest you!

Happy gardening,

Jessie Keith

Black Gold Horticulturist