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Viburnums -- Shrubs for Three-Season Interest
From a design standpoint, Viburnums are an important genus of plants in the garden for several reasons:
- they provide three seasons of interest (perhaps even four),
- they provide flowers in the spring or early summer, berries in the summer, fall, and into winter, and attractive leaf colors in the fall. Many of them also have interesting leaves in the summer.
- Some are also fragrant.
- I also like the fact that there are many species and cultivars to choose from so there is bound to be one or even two that fit a particular spot perfectly.
They are also important for their ability to be used in many different cultural situations.
- Depending on the species they can be planted in sun, part shade, or even in shady areas.
- Some viburnums will grow in dry soil, while most will accept periods of drought during the summer after they have been established.
Listed below are the viburnums which will grow well in our area. Some species are in my garden now, others used to be, and still others are on my list of plants to purchase. It's very important to place a plant in the right spot so I've included specific information on the cultural conditions
required for each species. The harder-to-find species (acerifolium, alnifolium, bitchiuense,
macrocephalum, cassinoides, molle, lantana, lentago, obovatum, x rhytidophylloides, and
seiboldii) have not been included. Also, there are some viburnums that are not hardy where we
live in Zone 6B of the Department of Agriculture Hardiness Zone Map. They are davidii,
japonicum, awabuki, odoratissimum, suspensum, tinus and they are not listed here as well.
Basically, viburnums grow in moist, well-drained soil and in sun. As I have mentioned before,
after establishing a viburnum for a year or two, it will take some drought. Usually the plant will
tell you by its droopy leaves when it needs water.
Here's the list of viburnum species, followed by the new "must-have" cultivars:
x burkwoodii - Burkwood viburnum is not a species but the result of crossing two different
species; therefore, the "x" is shown before its name. Grows to about 10x7ft. Its form or habit is
upright and multi-stemmed. Leaves are elliptic, pointed, slightly serrated, and 4in long. Fall leaf
color is wine red. The flower buds are pink. It has fragrant, white, snowball-type flowers. Its
fruit starts red and then changes to black but usually the plant doesn't produce much fruit. (This is a cross between carlesii and utile; both are listed below.)
'Mohawk' is the best known of the Burkwood cultivars. It's probably the best of the
fragrant snowball-type viburnums. It was selected for its dark-red flower buds, its
abundant blooms, strong fragrance, its resistance to disease and powdery mildew, and its
brilliant orange-red fall leaf color. It's also slightly smaller, growing to 8x8ft.
x carlcephalum - Fragrant viburnum grows to 10x10ft and its habit is open and loose. Leaves are
dark green, broadly oval, wavy, pointed and up to 5in long. Fall leaf color is red purple. Its
flower buds are pink. It has fragrant, snowball-type, white flowers up to 6in across. Its fruit starts
red then changes to black. (This is a cross between carlesii and macrocephalum var. keteleeri.)
carlesii - Koreanspice viburnum grows to 6x6ft into a dense, rounded shrub. The leaves are a
dull, dark green and a wide oval in shape. The leaves are slightly serrated, pointed and are 4in
long. Flower buds are pink to red. Its fragrant, semi-snowball, white flowers are 3in wide. Fruit
starts red and then changes to black.
'Cayuga' is an improved carlesii with improved resistance to disease and powdery
mildew, and beautiful pink buds. It was originally touted as compact and upright in habit.
It might grow quite a bit larger than that. I planted 'Cayuga' several years ago and it
appears to be a strong grower and will need pruning every few years.
dentatum - Arrowwood viburnum is a native shrub occurring naturally in eastern North America.
Grows to 10x10ft in a dense, rounded form. Its leaves are a lustrous dark green, broadly oval in
shape and pointed. The leaf's margins are coarsely serrated. Fall color varies from shrub to shrub.
Color could be yellow, red, or purple. Has white flat-topped flower clusters. Has oval blue or
blue-black fruit relished by birds. This viburnum grows well in sun to part shade and will sucker
with the plant growing wider with time.
'Ralph Senior' - Autumn Jazz® has glossy green foliage that turns yellow-orange-red-burgundy in the fall. Grows to 10x12ft in a vase form.
'Cardinal' has consistent brilliant red fall color.
'Perle Bleu' produces heavy crops of blue fruits and grows to 10ft tall.
'Christom' - Blue Muffin™ also produces a heavy crop of intense blue fruits and grows to about 7x7ft.
dilatatum - Linden viburnum grows to 10x8ft in an upright and open habit. Leaves are dark
green, often lustrous, and a broad oval with coarsely-toothed leaf margins. The leaves are 4 ˝in
long and are not sharply pointed. Fall leaves are russet red. Has creamy-white, flat-topped flower
clusters. This viburnum will grow in sun to part shade. Fruit is 1/3in long, red or scarlet, and very showy.
'Asian Beauty' is a new upright cultivar that keeps its glossy red fruit through the winter.
'Erie' grows to about 8x10ft wide and has good red to orange fall color. Its abundant red
fruits turn coral to pink after frost and stay that way through the winter. It is very resistant
to insects and diseases.
'Michael Dodge' has yellow fruit instead of the usual red and it grows to 5x6ft wide. Has
red fall leaf color.
farreri - Fragrant viburnum grows to 12x12ft in a loose, open habit. Its leaves are dark green,
oval, with edges serrated and pointed. Leaves are 4in long. Flower buds are pinkish red. Has
fragrant, white-tinged-with-pink flowers in a flat-topped flower cluster. It blooms before the
leaves unfold which helps to make the flowers stand out. Fruit is red changing to black when it matures.
'Nanum' is a dwarf cultivar growing only to 3x6ft wd. It has pink flower buds and white
flat-topped flower clusters. I grew this plant for several years but it was planted in the
wrong place and it died recently. I'm willing to grow this one again because of its
fragrance and size.
x juddii - Judd viburnum is said to be a superior carlesii with a full and rounded habit. Grows to
8x8ft. Leaves are dark green, oval to round, slightly serrated, pointed and 4in long. Its flowers are
white, fragrant, and snowball-type. Its red fruit changes to black. (carlesii x bitchiuense)
nudum - Smooth Witherod viburnum is a native shrub found in eastern North America. It grows
to 10x10ft in an upright form. Has lustrous, dark green, elliptic, pointed leaves. Its fall leaves are
red to red purple. Has creamy-white flowers in a flat-topped flower cluster. Its fruit is red to
purple.
'Winterthur' is my favorite nudum cultivar with lustrous, dark-green leaves and beautiful
pink to blue fruit with the different fruit colors appearing at the same time. This is an
upright plant and is said to be about half the size of the species.
opulus - European Cranberrybush grows to 15x15ft in a multi-stemmed, arching habit giving the
overall impress of a rounded shrub. Plant in sun or part shade. Its leaves are glossy, dark green,
deeply lobed, and grow to 4in long and wide. The fall foliage is variable being yellow-red or
red-purple. Has white lacecap-type flowers with white, fertile, inner flowers and showy, outer,
sterile flowers in flat-topped flower cluster. Its fruit is bright red.
'Compactum' - grows to half the size of the species and has excellent displays of flower
and fruit. Sounds like a perfect viburnum for smaller properties but is hard to find.'Leonard's Dwarf' - this is another compact plant very similar to 'Compactum'.
'Nanum' - is a great, small, low-maintenance deciduous shrub that should be used more
than it is. Grows to 2x3ft wide. This is a non-flowering and non-fruiting plant. Mine has
never flowered. Makes a nice low hedge or accent plant among flowers or ground covers,
and grows in bright shade.
plicatum - Japanese Snowball grows to 15x15ft in an upright form. Has dark green, broad oval,
ridged leaves coming to a sharp point. White sterile flowers are formed into a rounded, snowball-type cluster.
'Kern's Pink', 'Pink Sensation', and 'Roseace' - have pink snow-ball type flowers on a
6ft plant. I saw 'Kern's Pink' on a recent garden trip and thought it was a worthwhile
plant to have in the garden because of the unusual pink flowers for a viburnum.
plicatum var. tomentosum - Doublefile viburnum grows to 9x12ft in a horizontal form. Its leaves
are dark green and broadly oval and have a sharp point. Its flowers are non-fragrant, pure white,
lacecap-type flowers with white, fertile, inner flowers, and large, outer, sterile flowers in a flat-topped flower cluster. Has red-purple fall leaves and red fruit changing to black. Fruit is very
showy and devoured by birds during the summer. As it grows large, one way to control its size is
to cut it back to 12in high every few years.
'Shasta' is a very popular cultivar. It's wider than tall - 6x12ft wide. Its lacecap-type
flowers are 6in wide. The fruits are red changing to black as they mature.
'Summer Snowflake' is one of my favorite doublefile viburnums growing to 8x5ft wide.
Its leaves and lace-cap flowers are also smaller than the species, but it blooms off and on
through the summer even in a shady site.
'Watanabei' is another smaller growing doublefile. Its habit is dense and it flowers on and
off through the summer too.
The Doublefile viburnum is for me the star plant of the viburnums. It looks like a
dogwood when in bloom. This species does require some effort to grow it well as it is a large-growing shrub, needing a wide space. It is stunning in the spring with its beautiful white flowers
growing on wide, horizontally tiered stems. After flowering, the show goes on with its showy red
fruit sitting on top of its wide stems just waiting to be eaten by birds. In the fall it again puts on a
beautiful display when the leaves turn.
prunifolium - Blackhaw viburnum is a native shrub growing in eastern North America. Grows to
about 15x12ft in an upright to rounded form. Its leaves are broadly oval and pointed, dark green
in color, and grow to 3.5in long. Its flowers are creamy white and are in a flat-topped flower
cluster. Fall leaves are purple to red. Its edible fruit is pink changing to blue black. Plant in sun
or shade; it is adaptable in its soil requirements including dry soil.
x pragense - Prague viburnum grows to 10x10ft and its habit is upright to oval. It is said to be
extremely fast growing and needs pruning to keep it dense. Its evergreen, lustrous, dark green,
oval leaves are 4in long and are do not come to a sharp point. Flower buds are pink. Creamy-white, slightly fragrant flowers are in a flat-topped flower cluster. (This is a cross between
rhytidophyllum and utile)
rhytidophyllum - Leatherleaf viburnum grows to 15x15ft in an upright, multi-stemmed habit. Its
evergreen, long, narrow, dark green, leathery leaves are rough and grow to 7in long. Leaves are
only slightly pointed. Its flowers are lightly fragrant, creamy-white in a flat-topped flower cluster.
Its fruit starts red and changes to black. This viburnum tolerates heavy shade but needs protection
from wind.
'Cree' is more compact than the species and has lustrous, dark-green leaves growing to
about 6in long. Cree grows to about half the size of the species and the leaves do not curl
or roll in the winter as in the species. It produces lots of flowers and red fruit.
sargentii - Sargent viburnum grows to 15x15ft in a multi-stemmed, upright to rounded form. Its
green, strongly-lobed, maple-like leaves are up to 5in long and have a smooth, leathery texture.
Fall leaves are yellow to red. Has white lacecap-type flowers with white, fertile, inner flowers
and large outer, sterile, flowers in a flat-topped flower cluster. Its fruit is translucent bright red.
It's a vigorous grower and is more resistant to aphids than European Cranberrybush .
'Onondaga' has young foliage that is dark maroon with a fine, velvety texture. The
lacecap flowers have dark-red, fertile, inner flowers and large, white, sterile flowers
around the outside. Very striking! It is said to produce a rounded shrub to 6 feet high but
I saw a specimen last year that was much more upright.
Once I saw the two-color lacecaps on 'Onondaga' I had to have one for my very own.
Luckily I found one soon after and have been enjoying its smooth, lustrous leaves ever
since. It was too young to flower when I planted it. Hopefully it will flower next year.
Actually, even if it doesn't ever flower, I will enjoy it any way because its smooth leaves
are enjoyable to touch and stroke. (I visited a small arboretum some years back and came
across a V. sargentii and fell in love with its leaves after touching them. I asked the
arboretum guide what was the name of the plant but he didn't know. I knew at that point
that I had to have that plant and I've been looking for that smooth-leaved viburnum ever
since. This little story tells me and it might tell you that either I'm a plant nut or that the
smoothness and texture of plant leaves can be a very important aspect of a plant.)
setigerum - Tea viburnum grows to 12x9ft in an upright, multi-stemmed form. As the plant
matures it takes on a weeping habit which is very beautiful when properly placed in the
landscape. It has narrow oval, pointed, lustrous, dark-green leaves to 6in long. Leaves turn a
dark red purple in the fall. Has creamy-white flowers in a flat-topped flower cluster. The flowers
are secondary to its showy bright, warm-red fruit which lasts into winter because the birds don't
eat right away.
I have several plants of this species planted at the top of a hill with ground cover underneath
them. Hilltop siting is best because the stems eventually arch over and since we are looking at the
plant from below, we see a gorgeous spectacle in the fall and winter with the cascading plants
laden with bright red berries. Give it plenty of room and never cut back its stems as you will be
destroying this plant's beauty. As it ages, and as with most all deciduous plants, cut one-third of
the oldest stems back to the ground each year before new growth starts. In this way, there will
always be fresh, new growth with plenty of fruits for viewing and for the birds.
trilobum - American Cranberrybush is a native shrub naturally found in eastern North America. It
grows to 12x12ft in a dense, rounded form. Its lustrous, medium-to-dark-green, lobed, maple-like
leaves come to sharp points. Fall leaf color is yellow to red purple. Its leaves are lacecaps with
white, inner, fertile flowers and white, outer showy, sterile flowers in a flat-topped flower cluster.
Its fruit is bright red and very showy.
'Red Wing' is smaller growing to 8x8ft. It has reddish new leaves and red leaf stems, or
petioles, which remain throughout the season. In the fall the leaves turn bright red to wine
colored. The bright red fruits are persistent through the fall and winter.
'Compactum' is a compact cultivar that is just perfect for smaller gardens because it
grows only to half the size of the species.
'Bailey Compact' is another smaller-sized cultivar that has a deep red fall foliage and
grows to about 5x6ft wd.
utile - Service viburnum grows to 6x6ft with an open habit. Leaves are small, oval, wavy,
evergreen, and lustrous dark green. Flower buds are pink. Has slightly fragrant, white, flat-topped flower clusters. The fruit is bluish black. Many great cultivars have utile as one of its parents.
Among the best is:
'Conoy' is a spreading evergreen shrub with small, glossy, dark-green leaves and growing
to 5x8ft. The dark pink flower buds open to slightly fragrant, white flower clusters.
Fruits start red and change to black at maturity.
I hope I have peaked your interest in viburnums. There are so many of them, that I'm sure you'll
find the perfect viburnum for that garden space of yours.
Viburnum Characteristics
Also, all viburnum species have similar characteristics that show that they are related to each other. The first
one is that they all have "simple" leaves with a leaf bud appearing at the point or "axil" where
the each leaf is attached to the stem. Other examples of "simple" leaves are maple, beech, and oak. See example:
Another characteristic of all viburnums is that two leaves are "opposite" meaning that the leaves
and their buds are directly across from each other on the stem. See example.
Another characteristic is the shape of the leaf which in viburnums tend to be "ovate" or "elliptical". And yet another characteristic is that the margins of the leaves tend to be "serrate", "incised", "undulate", or "lobed".
As to flower shape, all viburnums have a "cyme" type flower configuration which is a wide-spreading group of small and/or large flowers at the end of the flower stalk with the inner flowers
opening first. Dogwoods and viburnums are examples. The cymes are either snowballs or semi-snowballs (similar to the summer-blooming PeeGee Hydrangeas), lacecaps (as in the flat-topped
hydrangeas such as "Tokyo Delight" with tiny, fertile flowers in the center and larger, showy,
sterile flowers on the outside), and flat-topped flower clusters made up of all tiny, fertile flowers.
To learn more about plant structure and morphology, try one of these websites:
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