With their attractive foliage, distinctive horizontal forms, showy fruit and abundant, often-fragrant flowers, viburnums are essential additions to the garden. This diverse group of shrubs is also amenable to most soil types. (Average, heavy loam with adequate moisture is ideal, but many species are tolerant of drought and drier conditions.) Many also seem to come with "antifreeze" in their plant veins—cranberrybush, for example, is hardy to Zone 2.
Viburnums vary widely in height, ranging from 60 centimetres to six metres, making it easy to select the right one for any situation. North American native species such as V. lantanoides, V. dentatum, V. lentago, V. prunifolium and V. rufidulum, for instance, mix naturally with more exotic viburnums and with many other shrubs.
Some have showy spring leaves and colourful fall foliage in yellows, oranges or reds. A few are evergreen or semi-evergreen in Zones 6 and higher (e.g. V. x rhytidophylloides 'Alleghany', V. 'Pragense' and V. rhytidophyllum), providing season-long interest in the garden.
The striking "wedding cake" form of the doublefile types (see chart, page 34), with their flowering and fruiting tiers, is spectacular. Like most of their relatives, these viburnums are very tolerant of wet, dry, acidic or alkaline soils and sunny or partly shaded conditions.
• site in full sun or part shade for best results
• prune only to remove branches that are damaged
• remove spent blossoms after flowering to encourage improved blooming the following year (will sacrifice the current season's fruit)
Name: 'CONOY' VIBURNUM (Viburnum x burkwoodii 'Conoy') ZONE 5
HxW (m): 1.5 x 2.5
Form & Foliage: Compact, with dark green, glossy leaves; fragrant, white, flat-topped blooms in spring; evergreen in Zones 7 and 8, where foliage can be tinged with maroon in fall and winter
Fruit: Showy, persistent, pendulous red fruit in late summer, maturing to black in late fall
Name: DAVID VIBURNUM (V. davidii) ZONE 7
HxW (m): 1.5 x 1.5
Form & Foliage: Pink buds open into creamy white, rounded blooms; leathery evergreen foliage turns orange-red or purple in autumn
Fruit: Pinkish red fruit ripens to metallic blue and black; fruit attracts wildlife; plant two or more for good pollination
Name: NANNYBERRY (V. lentago) ZONE 2
HxW (m): 4 to 7 x 3 to 4
Form & Foliage: Upright, multi-stemmed, open crown with arching branches; creamy white, round-topped flower clusters in spring; shiny, dark green, deciduous leaves
Fruit: Dark blue-black fruit ripens in fall on red stems that persist into winter; attracts birds