Common name: Chinese Dogwood
Cornus alba and C. stolonifera are generally grown for their autumn foliage, and colourful yellow, crimson and or almost black-purple stems.
C. florida, C. kousa and C. nuttallii are grown for their autumn colour,and large white or pink bracts that are produced in early summer.
Cornus are deciduous trees that can grow to in excess of 6m (20ft) high with a similar spread if left unattended.
Some prostrate varieties can be used as ground cover.
Week 10-15: Plant out bushy species in moist soil, in sun or partial shade.
Week 20: Plant out cuttings taken the previous year into a nursery bed, or pot up into 125-150mm (5”-6”) pots of potting compost and grow on for two or years prior to planting out in their final quarters.
Week 28: Take 75-100mm (3”-4”) long heel cuttings from half-ripe laterals.
Insert the cuttings in equal parts (by volume) peat and sand and root at a temperature of 16°C (60°F).
Mist the cuttings daily to prevent dehydration.
Pot the rooted cuttings in to 70mm (3”) of potting compost and over-winter in a cold frame.
Week 32: Collect seed when ripe and sow into pots or pans of seed compost and place in a cold frame to stratify during the cold winter months.
The seeds may take 18 months to germinate.
When the seedlings are large enough to handle, set them singly in 70mm (3”) pots of potting compost and grow on in a cold frame.
Grow on for two or three years before planting out.
Week 33: Layer suitable low growing stems.
Week 35–45: Plant out the tree species in fertile, humus-rich, neutral-acid soil in a position that gets plenty of sun to ripen the wood.
It will tolerate partial shade but its foliage and stem attributes might not appear as good as those that are grown in full sun.
Plants are initally slow-growing until they settle in and become established, after which growth speeds up.
Keep pruning of flowering varieties to an absolute minimum.
Dead wood should be removed after flowering.
Species grown for their coloured bark can be cut hard back to within a few inches of the ground circa Week 16.
Pests and Diseases
Cornus are rarely affected, but can sometimes suffer from Cornus anthracnose and honey fungus.
anthracnose is a fungal infection that is more prevalent in cool, damp weather.
The symptoms consist of spots on the leaves in late spring.
Affected branches should be pruned out and burnt.