|Official Plant Name||Cornus|
|Plant Type||Trees / Shrubs / Hedging|
|Toxicity||Some edible fruits|
|Foliage||Dark-green, deciduous, ovate leaves|
|Flowers||Distinctive white flowers|
|When To Sow||May, June, July, August, September|
|Flowering Months||March, April, May|
|When To Prune||March|
Full Sun or Partial Shade
Exposed or Sheltered
1.5 – 2.5M
1.5 – 2.5M
Most soil types
Moist but well-drained
Want an ornamental tree for a postage-stamp-sized landscape in your garden? One that will provide virtually year-round colour?
Well, a Dogwood Tree will offer richly-hued de facto flowers for a couple of months. Bright scarlet berries, most of them edible, will follow.
Autumn will produce blazes of reds and purples, and winter will bring lovely branching forms or highly-textured bark into view. What a deal!
If you want several garden landscape trees with notable ornamental value and which will provide year-round interest, look no further than Dogwood Trees. Half-a-dozen Dogwood varieties is all you need!
Glossy or variegated foliage, thick clusters of spring ‘flowers’ in rich creams or pinks, followed by colourful and edible berry-like fruit, then blazes of striking hues in autumn, and finally a display of the highly-regarded branching patterns in winter, while some species produce late-season fruit.
Some species are even appreciated for their eye-pulling, textured bark. And this is only a general outline – virtually each variety of Dogwood Tree brings its own very special ornamental value and visual appeal to the garden.
Dogwood Trees belong to Genus Cornus but not all Cornus are Dogwoods as such, for Dogwood Trees are a subset of this genus which is further composed of much-branching shrubs and also a few rhizomatous subshrubs.
However, there is no hard-and-fast line between Cornus trees and Cornus shrubs because several species or cultivars can be either a tall shrub or a small tree depending on whether or not the specimen is pruned, and how it is pruned.
The total number of species in Cornus number about 50 (not including hybrids and cultivars). Most of them are deciduous but a few are evergreen.
Varieties of Dogwood trees differ in the colours and types of their small or insignificant flowers encircled by much more attractive and colourful bracts, the hues and edibility of their berries or drupes, and by the kind of colours they may display in autumn.
The simple leaves are usually ovate and opposite, and of a mid-green to dark green tone.
Most Dogwood Trees are quite slow-growing even though they are not overstorey trees or particularly tall trees – many Dogwood varieties including very popular Cornus Kousa and cultivars reach heights of only about 7 metres and even most of the taller ones usually attain heights of 10 to 12 metres.
Some species take ‘only’ 20 years to attain their ultimate height while others take 30 and even 40 years. As a result Dogwood wood is of a superb quality, being strong and dense. It is also desirable for its pretty grain patterns.
This wood is much valued by artisans for crafts, carving, and parquetry, and is also used when small but strong wooden material is required, such as for tool handles.
Background and Origins
After the advent of Civilized Man many millions of years after Cornus trees, he made practical use of these trees.
Native Americans used Cornus bark and leaves for fever, colic, and other medical purposes and, probably learning from the original inhabitants, early American settlers adopted the practice too.
On the other side of the world, extracts from Cornus species are used in traditional Chinese medicine to treat various ailments.
Cornus is quite a cosmopolitan genus. Species are native to all of North America, Europe, and nearly all of Asia except for Kazakhstan and its surrounding countries and India.
Species also grow in regions of Eastern-Central Africa and the north-western hump of South America. All of the desirable Dogwood Tree varieties are Far Eastern or American ones.
Dogwood Trees are cherished in many regions of the United States and some even claim it for their own, as has Virginia: a Dogwood species, Cornus Florida, is the state tree and its ‘bract flower’ is the state flower.
The aim of this section is not to list the most popular or most desirable varieties, and it is certainly not meant to provide an exhaustive list.
Rather, the intention is to illustrate the enormous diversity in size, form, and seasonal display of colours. By ‘flowers’ we refer to the more attractive colourful bracts.
C. Kousa or just ‘Kousa’, originating in China, Japan and the Koreas, is the species from which the majority of the most popular and desirable cultivars descend. It typically reaches a height of about 7 metres. In spring it produces a lush display of greenish-white flowers that are often pink-tipped, with light red berries following in summer. In autumn there is another lovely display of deep reds and purples. In winter this species’s patchy, somewhat scaly, tan-coloured bark comes into view.
C. Kousa var. chinensis ‘Wieting’s Select’ also grows to about 7 metres. Its flowers are pure white, developing pink edges and tinges, and the late summer berries are a saturated tone of pink. In autumn the foliage puts on an amazing show of deep, rich reds.
C. Kousa ‘Miss Satomi’ grows to your choice of a small tree of 4 to 5 metres or a tall shrub. It is covered by candy pink flowers in summer. More colour follows in autumn as the (inedible) fruit and the foliage both present attractive tones of light and rich reds. RHS Award of Garden Merit
Many other Kousa cultivars are available, ranging in height from 4 to 8 metres, and producing foliage, flowers, and berries in various appealing light and dark colours.
C. foemina or Stiff Dogwood also gives you a choice between growing it as a small tree of 6 to 7 metres or a tall shrub. Its flowers are white and relatively small and in autumn the foliage display includes deep and rich hues of wine red and purples. But the twist on this tree is that its late summer berries are blue, and a popping tone of blue at that.
C. florida or Flowering Dogwood is the ‘main’ American species. It grows to about 7 metres. In mid spring it starts to produce an abundance of white or pinkish flowers, followed by vermilion or light red berries in late summer. Autumn brings a blaze of reds and purples as the foliage changes colour. This species is, unfortunately, the most susceptible to cornus anthracnose.
C. florida ‘Sunset’ grows to about 7 metres and ‘improves’ upon the mother species in both foliage and flowers. The leaves are wonderfully variegated, being bright green in the centre with a substantial edging of bright yellow. Late spring and early summer bring bright pink flowers, often with white flushes. The late summer and early autumn show comprise of red berries, with the foliage turning reddish-purple as the season progresses.
C. controversa or Giant Dogwood lives up to its name – at least where Dogwoods are concerned! – reaching 15-metre heights. It has a wonderful tiered branching pattern that can be observed in winter when the tree is bare but admired even more when it is in flower. And those flowers are plentiful and of a very rich creamy shade. Autumn brings different colours as the berries on this tree are blue-black while the leaves display shades of purple and violet.
C. controversa variegata or Wedding Cake Tree is a miniature version of C. controversa, topping out at about 3 metres. This dinky tree also has that wonderful tiered branching pattern. The leaves are variegated – green in the centre with thick cream edges. The late spring to early summer flowers are white-white and the berries following them in late summer and early autumn make the strongest of contrasts with their bluish-black colour. RHS Award of Garden Merit.
Where to Plant Dogwood Trees
As understorey trees, Dogwoods are quite comfortable in part-shade locations. However, the sun-shade preference depends on the particular variety and also the climatic zone that that variety is planted in.
In most regions of England, siting Kousa varieties in dappled sunlight or afternoon shade would be preferable over full sun.
At the same time, do not plant them in full shade which would be worse than full sun. American-native Cornus varieties should be sited in full sun, otherwise partial sun.
As smaller trees with shallow roots, Dogwood Trees need to be watered. The sunnier their location and the hotter the weather, the greater their requirement for water, both in amount and frequency.
Dogwood Trees may be called landscape-ornamental trees; they are not shade trees and certainly not tall trees, and should be sited accordingly.
Depending on the particular variety of Dogwood Tree, it can be planted in front of a dwelling or behind it, at the boundary of a property, or at the rear of flowering bushes.
With hardiness ratings of Zone H5 or H6, all Dogwood Trees are hardy throughout the United Kingdom.
Feeding, Care and Growing Tips
Cornus trees can be propagated in any number of ways: from seed, softwood cuttings, semi-hardwood cuttings, hardwood cuttings, grafting, and even suckers, each method in the season-appropriate and suitable to it.
Virtually every variety of these trees can be propagated by at least two of these methods.
Propagating Dogwood Trees from seeds is troublesome and is a method best left to experts; also trees grown from seeds take several years to mature. Grafting is the method of choice but this method also requires expertise.
Though you can grow some Dogwood Tree varieties from cuttings without much difficulty, you will have to match the method to the variety as well as the season, after which you will need to prune correctly and watch over it patiently as it will take years to mature.
Amateurs and home gardeners will typically get Dogwood Trees as a potted plant or bare root plant. If you have a choice between the two, opt for a potted plant even though it will cost more.
The best soil for Dogwood trees is a loose, fertile one that drains very well. Densely-packed or heavy soils are unsuitable. Sandy loam amended with organic humus, compost, peat, or some combination thereof would be perfect. It may have a layer of gravel or perlite.
Dogwood Trees prefer acidic soils. Cornus Florida and other American-originated varieties require acidic soils; they will not thrive in close to neutral pH soil.
They require soil pH in the Moderately Acidic to Slightly Acidic range – 5.6 to 6.5 (which may be a little lower but not a little higher). Cornus Kousa and its cultivars also need acidic soil but the Slightly Acidic to Neutral range is best for these varieties.
Ideally, potted Dogwoods should be transplanted during mid-winter to mid-spring. Do not transplant them in autumn.
Many potted Dogwoods are grafts.
Try to spot the graft and plant the tree so that the graft line is well above the soil level otherwise the tree will revert to the rootstock or may even die. The most straightforward way to go about it is to plant it to a soil level matching that at which it was in the pot.
Otherwise, if you get a bare-root tree, plant it to about three-fourths of the root ball, keeping about a quarter of it above ground.
Do not store a bare root Dogwood after you receive it. Unpack it immediately, examine the root system for problems, and set it in a large bucket of water for the root system to soak for 12 to 15 hours prior to planting.
After transplanting a potted tree give it a heavy watering. Give a bare root specimen whose roots had been soaked a moderate watering.
Keep in mind that Dogwoods are shallow-rooted trees; therefore, they should be watered periodically and consistently.
They are not drought-tolerant trees. The amount of the sun and extent of the heat would dictate the amount and frequency of watering.
You will need to be more attentive to the water needs of developing and young trees than mature and established ones.
At the same time be sure that the roots do not get waterlogged and that the soil drains well.
Dogwood Trees do not need fertilising, especially if your soil is fertile and has organic content, but if you must, fertilize only from its third year.
Fertilise in early spring using a lighter-than-recommended application of 12-8-8 liquid fertiliser.
Mulching around the base will be helpful no matter what region you are in.
In warm, sunny climates, it will keep the soil moist for longer; in frigid climates it will protect the roots during hard frosts.
Pruning Dogwood Trees
Dogwood Tree varieties require little, if any, pruning and some should not be pruned at all. (Be aware, though, that if you wish to grow a Cornus shrub as a miniature tree, you will need to choose a leader, pinch out competing stems, and let the leader develop to the fullest.)
For the most part, all you need to do is to prune dead, broken, or diseased branches (such branches must be removed). Other than that, you should prune when two branches are crossed and touching one another.
If you see a branch emerging from the base of the tree, this too should be pruned for cosmetic reasons.
All pruning should be done in winter and no later than early spring.
Larger branches should be pruned using the Three-Cut Method.
Be very careful about removing any suckers attached to the trunk of the tree as you do not want to cause a wound on the trunk.
Suckers observed on the nearby ground may be removed in winter or the sucker shoots may be mowed over during any season.
Common Diseases and Problems
Dogwood Trees are generally very pest-free trees.
The Asiatic varieties plus C. nuttallii and, particularly, C. Florida and its cultivars (but not other American species) are susceptible to cornus anthracnose. It is a fungal disease that causes blotches on leaves and defoliation, and dieback of stems.
Cornus anthracnose cannot be treated by the hobbyist gardener; this disease calls for the attention of a professional botanist or horticulturist.
Fallen leaves and affected parts of the tree should be removed and destroyed.
You can avoid fungal diseases, root rots, and such by ensuring that the tree is planted in the right type of soil, that the soil pH is not alkaline, it is not sited in full shade, and the soil does not stay damp or waterlogged.
Where to Buy Dogwood Trees
In the United Kingdom you may find that Cornus multi-stemmed shrubs and bushes are much more widely available than Dogwood Trees.
However, you are sure to find a few of the more popular varieties such as C. Florida and some C. Kousa cultivars at most brick-and-mortar garden centres.
You will find a very wide choice of potted Dogwood Trees at online merchants that specialise in bushes and trees.
Kersie learnt the basics of gardening as a toddler, courtesy of his grandfather. In his youth he was an active gardener with a preference for flowering plants. He is a professional and vocational writer and his freelance projects have spanned various kinds of writing.