There are approximately 225 species.
Some are used as hedging (eg. V. tinus), screening plant (V. odorattissimum), tub plant, shrubberies.
They tend to grow best in temperate climates but many varieties can grow well in the subtropics.
Many are widely grown for their attractive, often fragrant flowers, and/or attractive berries. Some of the deciduous species also have attractive autumn foliage.
Most plants produce dense specimens.
They may be either deciduous or evergreen. Most are shrubs although there are a few small trees. They have simple leaves, arranged opposite on stems, small flowers, commonly white or pinkish, massed in heads.
Some have good autumn foliage. Berry fruits on some are attractive and attract birds.
They do well in a range of soils from clay to ordinary soil types, provided waterlogging and long periods of dryness are avoided. Optimum growth is achieved with moist, rich soils, and a protected position with part shade. Some prefer cool to temperate climates, a few are suited to warmer frost free climates (e.g. V. odoratissimum, V. japonicum).
You can prune as desired for shaping, responds to occasional feeding and freely watering in dry periods.
Annual feeding (with medium doses of well composted manure), and yearly pruning to shape are beneficial.
Some viburnums (eg. Viburnum Opulus), have berries which attract birds; which in turn eat pest insects. Foliage from deciduous species create a nutritious cover of leaf litter for under plantings. Evergreen species (eg. V. tinus) often have dense foliage which will effectively suppress weeds.
Propagate by cuttings
Serious pest or disease problems are rare. Occasionally thrip, mites, scale or leaf spot diseases.
V. Carlesii -deciduous, to 1.8m tall, fragrant white flowers.
V. japonicum – evergreen to 2m with leathery shiny top-surface leaves and fragrant white flowers in early summer.
V. Lentago – Tall deciduous plant that is kept short by pruning, white flower clusters up to 13cm across.
V. odoratissimum - evergreen tall shrub up to 3m. Very dense growth and large thick green leaves. White clusters of slightly fragrant flowers in spring for a short period.
V. Opulus -deciduous to 3m tall, maple like lobed foliage, white flowers to 10cm across, several named varieties with varying flower colours.
V. Opulus compactum – dwarf growing habit.
V. plicatum – Large deciduous shrubs to 3m with ovate grooved leaves and white globular flower clusters.
V. plicatum ‘Lanarth’ – Deciduous plant up to 3m with white flowers.
V. plicatum ‘Mariesii’ – striking layered effect of white sterile blooms.
V. Tinus -evergreen to 2.5m tall, white or pinkish flowers, various named varieties.
V. Veitchii -deciduous, to 1.8m tall, white flowers, red fruit mature to black.
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