Cornus
A hardy, easy to grow, group of shrubs and small trees that provide all-year-round interest and colour in the garden.
The common varieties are mainly planted for their brightly coloured stems, bringing much needed colour in winter. Less common varieties are grown for their attractive flowers and foliage.
Family: Cornaceae
Botanical Name: Cornus (kor-nus)
Common Names: Dogwood, cornel.
Foliage: Evergreen
or deciduous simple green leaves. Deciduous forms usually
provide good autumn colour. Several variegated leaf
forms are available. Many forms have brightly coloured
young stems.
Flowers: Dense clusters of tiny white
flowers. Some types have showy bracts.
Flowering Period: May and June.
Soil: Moist but
well-drained soil (clay, sand or loam). Acid
or neutral pH.
Conditions: Full
sun or partial shade. Best grown in a south,
east or west-facing aspect, in either a sheltered or
exposed location.
Habit: Bushy,
suckering.
Type: Shrub or small tree.
Origin: Eastern Europe, Siberia and
northern temperate zones.
Hardiness: Most dogwoods are fully
hardy in the UK (down to -15°C)
Planting and Growing Cornus
Plant in any good fertile garden soil, in full or partial sun. Except for a few of the species with colourful bracts, they are happy in most soil types and many will even survive waterlogged conditions. Most forms are also shade and pollution tolerant.
Plant outside in early autumn or
spring. Container grown plants can be planted outside
at any reasonable time of year.
Dogwoods with coloured bark should be sited where
they can
be seen to best advantage in winter. Those with variegated
leaves are best positioned where
they will stand out against darker foliage or to brighten
up a dark corner. Varieties with colourful bracts are
ideal for mixing in with other trees and shrubs.
Taking Care of Cornus
Water thoroughly during dry weather until well established. Mulch with organic matter in spring and apply a general fertilizer suitable for shrubs.
Pruning Cornus
The majority of species require little or no pruning. Flowering forms are best left unpruned.
Varieties grown for colourful stems, such as C. alba, should be cut hard back in the spring, to within a few inches of the base. This will encourage fresh young stems that provide the best colour.
Pests and Diseases
Generally pest and disease free.
Propagating Cornus
Most varieties strike easily from cuttings taken in summer or by layering. Hardwood cuttings can also be taken in autumn. C. canadensis can be propagated by division.
Seed can be down in the autumn but the results are often poor.
Popular Varieties of Cornus Grown in the UK
Coloured Stems
Cornus alba is a quick spreading shrub, available in a range of cultivars, all with long red stems.
Cornus alba 'Elegantissima' has grey-green leaves with creamy white margins.
Cornus alba 'Aurea' has attractive golden yellow leaves. It has plain green leaves in summer, turning vivid red in winter.
Cornus alba 'Sibirica' is loved for its impressive bright red stems.
Cornus alba 'Spaethii' has bright yellow leaves and bright red bark in winter.
Cornus alba 'Variegata' has lovely white and green variegated leaves.
Cornus sanguinea (common dogwood)
has red or purple stems. The white scented flowers
appear in June,
followed by black fruits in autumn.
Cornus stolonifera (Red osier dogwood) is very vigorous species with excellent autumn colour.
Cornus stolonifera 'Flaviramea' is a deciduous shrub with tall greenish yellow stems. Suckers freely. Height to 8ft (2.4m).
Small Trees
Cornus mas (Cornelian cherry) produces tiny bright-yellow flower clusters in early spring before the leaves appear and attractive fruits in the autumn. Height to 6ft (1.8m), spread to 5ft (1.5m) or small tree to 15ft (4.5m). Cultivar 'Aurea Elegantissima' has leaves with a yellow border, sometimes also tinged pink.
Flowering Shrubs
Cornus florida is a large shrub with large white bracts. Several good cultivars are available. Height up to 16ft (5m).
Cornus florida 'Rubra' has rosy pink flowers.
Cornus kousa 'Chinensis' is a large flowering shrub with creamy white bracts. It produces edible red, strawberry-like fruit in good summers and bright red autumn leaf colour. Prefers light shade. Dislikes alkaline soil.
Cornus nuttallii (Pacific Dogwood) has large white bracts, around 6in (15cm) long.
Ground Cover
Cornus canadensis is a low growing form that makes excellent ground cover, especially in shady positions under trees and other shrubs. The flowers are insignificant but the surrounding white bracts provide colour and interest in June, followed by red berries. Height to 8in (2cm), spread to ft (m).