Cornus alba, the white dogwood that’s actually pretty red… and green… and white!

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Flat, creamy-white flowers open from the end of spring, clusters of little white berries follow, and the bright green leaves turn orange-red before the young stems glow red all winter. White dogwood (Cornus alba) is a fast-growing, very hardy shrub that suits almost any soil, as long as it drains well — then it answers many ornamental challenges single-handedly.

Short presentation of Cornus alba

White dogwood is a fast-growing shrub. Several things make it a remarkable choice for the garden:

• its flat, creamy-white flowers that appear from the end of spring until summer, followed by clusters of little white berries;
• its arched, semi-weeping bearing;
• its young stems that are a showy red color in winter;
• its bright green, oval leafage that turns to orange-red as fall draws near.

These features make Cornus alba a precious ally when landscaping a garden, since it single-handedly answers many ornamental challenges.

From the more famous white dogwood varieties, let’s mention:

• ‘Aurea’ and its foliage that’s sun-yellow in spring before slowly shifting to green;
• ‘Elegantissima’ with green leaves wreathed in a thin creamy-white variegation;
• ‘Sibirica’, which boasts winter stems that are even redder than that of other varieties Cornus ;
• and, lastly, the ‘Sibirica variegata’ cultivar, which is a combination of both the ‘Elegantissima’ for the leaves, and ‘Sibirica’ for the red stems.

Take note that Cornus alba is a toxic plant, its fruits may cause stomach pain if eaten. Leaves themselves are also irritants for some people.

Which Cornus alba variety to choose

The four best-known white dogwoods differ mainly in their leaves and in how red their winter stems turn. Use the table to match a variety to the effect you are after.

Whichever you pick, remember that varieties grown for their foliage show their colours best in full sun.

Planting white dogwood

Cornus alba can be planted both in fall and in spring. Not the picky type, it will grow satisfactorily in any type of soil, as long as it drains well.

Though all varieties cope fine with part sun, those that feature ornamental foliage will shine more in full sun.

The planting doesn’t require anything specific in terms of preparation, just:

• Dig a planting trench about 8 to 12 inches wide and deep (20 to 30 cm).
• Amend the soil with a little soil mix to bolster your white dogwood’s growth.
• Tease the pot away, and break the root ball up to spread a few roots out.
• Settle the tree in the hole, and backfill the hole, pressing the soil down well.
• Water abundantly.

Note that the tight bearing of Cornus alba and the fact that it is very resistant to hard pruning make it very suitable for growing in pots. In this case, just settle it in a container that’s large enough with holes at the bottom for excess water to drain out of. Also, before positioning your sapling, spread a drainage layer at the bottom of the pot, without impeding flow of water through the holes. You can use clay pebbles, gravel, broken pot shards, etc. What matter is that water can’t linger in the pot.

Caring for Cornus alba

Watering

Not a time-consuming plant, white dogwood won’t need much care.

• Simply make sure you properly water young specimens during the summer.
• Check on whether the leaves are wilting, that’s a sure sigh the plant needs water.

Pruning/Trimming

As for pruning your Cornus alba, it tolerates pruning perfectly.

• You can thus prune it every year, at the end of winter, if you wish for it to stay dense and compact.
• Also consider removing old wood right from the stump, to trigger appearance of new shoots.

Propagating Cornus alba :

Cornus alba naturally creates offshoots. Indeed, it’s common to see new stems appear near the mother plant’s trunk. This may cause it to turn invasive if you don’t intervene, but it’s also a great way to create new plants. Simply chop off the young offshoot right under the roots and transplant it elsewhere.

Know that it’s also possible to succeed with other techniques like cuttings and layering.

Diseases and pests on Cornus alba

Though pests don’t seem attracted to white dogwood, it might be infected by dogwood anthracnosis (Discula destructiva), a disease caused by a fungus. Symptoms first appear on leaves: brownish-rust-like spots that evolve into necrotic tissue. If left unchecked, these spots migrate to appear on new growth and on stems.

The solution is to remove and burn any sick portion, and even the whole plant if it’s completely overrun.

Landscaping uses and companion plants

Versatile Cornus alba fits right in for nearly every form of landscaping:

• Standalone, in the middle of a garden or in a flowerbed; best select a variety that has special foliage or winter bark.
• In a group to form a shrub bed; it looks great together with other ornamental shrubs such as yellow-wood corkscrew willow (Salix x sepulcralis ‘Erythroflexuosa’) and other dogwoods with colorful bark, assembling several species and varieties.
• To decorate a deck or terrace, when planted in a pot.