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Fire up the Landscape with Red Twig Dogwood

The bloodtwig dogwood ‘Midwinter Fire’ has some of the most brilliant branches for winter.

Fiery branches of gold, orange, and red rise from the winter garden, bringing color to the bleakest landscapes. There’s no better complement to evergreen and berried landscape shrubs than brilliant red twig dogwoods (Cornus sericea) and blood twig dogwoods (Cornus sanguinea). Their branches also look attractive in seasonal arrangements.

About Redosier Dogwoods

The fruits of redosier dogwood

Native to much of North America, redosier dogwood is a remarkably hardy, densely branched shrub (6-12’), growing as far north as Alaska where it survives in USDA Hardiness Zones 2-9. It naturally grows in moist areas or watersides and can even withstand slightly salty soils. It may exist under the shaded canopy of trees or in open sunny areas. In spring, it produces flat-topped clusters of white flowers. These are followed by whitish, berry-like fruits that appear later in the season. The bright green leaves turn shades of wine red or maroon in fall. The younger twigs of wild plants naturally turn shades of red in winter.

The bloodtwig dogwood is just as pretty, but it is Eurasian, inhabiting forested regions and wetland margins from northern Europe to western Asia. It performs in the landscape much like redosier dogwood, but its late-season fruits are black rather than white.

Redosier Dogwoods and Wildlife

Spring azure butterfly caterpillars feed on redosier dogwood foliage. (Photo by D. Gordon E. Robertson)

The redosier dogwood has a unique relationship with certain pollinators. The flowers are visited by bees and butterflies, but the foliage is also the larval host of the spring azure butterfly, a beautiful blue butterfly found across much of North America. The bloodtwig dogwood also serves as the larval host plant to the less desirable casebearer moth. Many birds feed on the fruits and rely on the dense branching of these shrubs for nesting and shelter.

Varieties

The yellow twigged Cornus sericea ‘Flaviramea’ has pretty golden twigs in fall.

For brilliant twig color, few redosier dogwoods can beat the classic variety ‘Baileyi’. Its brilliant red branches glow in winter, and the dense shrubs reach up to 9’. A comparable cultivar is ‘Cardinal’, which offers good diseases resistance in addition to red twig color. The more compact redosier dogwood, Arctic Fire®, is a shorter form (6’) that has equally bright red stems. The equally compact bloodtwig dogwood, Arctic Sun®, has golden twigs tipped with orange and coral red, as does the slightly taller ‘Midwinter Fire’. The dwarf redosier dogwood ‘Kelseyi’ (3’) is the smallest of the red twig forms.

Yellow-twig forms are also striking. The best of these is ‘Flaviramea’ (8’), which develops bright yellow to greenish yellow twigs in winter.  The pretty ‘Silver and Gold’ is a variant of ‘Flaviramea’ with attractive variegated leaves edged in silver, in addition to yellow twigs. Another variety with handsome variegated foliage is ‘Hedgerows Gold’, which has golden-edged leaves that line deep red branches.

Planting

Cornus sericea Arctic Fire® (Proven Winners)

Twig color and growth is best when plants are planted in a sunny to partially sunny location. Choose a spot where the winter twigs will be most conspicuous—either an open area or against a darkly colored mass of evergreens or a substantial foundation. Mass plantings have the best winter effect and are great for stabilizing slopes or watersides.

Soil can be moist or well drained, but fertile soil with a pH of 5.0 to 7.5 is preferred. When planting a new shrub, dig a hole that is twice the size of the shrub’s root ball. Amend your backfill with Black Gold Garden Soil before planting, and set the shrub in the hole, making sure the root line and soil line are level. Fill in along the edges, and pack the soil down firmly to ensure good root-to-soil contact. Irrigate well after planting, and make sure newly planted shrubs stay well irrigated during the summer months.

Pruning and Maintenance

Cut old, overgrown branches to about 1-2’ from the ground.

The best twig color comes from younger branches, so it is important to regularly prune redosier dogwood in later winter to early spring. Cut old, overgrown branches to about 1-2’ from the ground to keep shrub height in check and encourage new growth. Pruning cuts should be made at a 45-degree angle. It is important to dip pruners in a 10% bleach solution when pruning each new shrub to avoid any chance of spreading common diseases.

Diseases

Close up of Septoria leaf spot. (USDA Forest Service)

Dogwood stem canker (Botryosphaeria dothidea) is the most notorious disease of these shrubs. It is a fungal disease that causes cankers and branch death. The disease enters the plant via cuts and lesions, which is why it is important to keep pruning tools clean when making cuts. Plants that become stressed are most susceptible to the disease.

This canker is manageable. Remove diseased stems by cutting several inches below the point of infection. Do this in dry weather and clean pruners between cuts. Remove and destroy diseased branches. Irrigating shrubs during dry spells will reduce stress and help ward off the disease. Choosing canker-resistant varieties, such as ‘Cardinal’ is also useful.

Septoria leaf spot is another common disease that causes unsightly black spots and early leaf shed on the summer leaves of red osier dogwood. The lower leaves are the first to show spots. Several cultural steps can help to control Septoria leaf spot. First, thin overly dense branches to encourage airflow and reduce the chance of infection. The disease overwinters on infected leaf tissue, so remove all fallen leaves underneath the plant.

Redosier dogwood is a true landscape gem. Keep it well maintained, and it will reward you with bright warm color on cold winter days.

 

Plants For the Winter Garden

The fragrant flowers of wintersweet can withstand even the harsh winter weather.

In the Pacific Northwest, the garden in winter can be a bit bleak. I know mine certainly is. However, the more I talk to other gardeners and visit other gardens at this time of year, the more color I see. Often the color is not from flowers, but from bark, foliage and stems.

For the last few years, I am been striving to add more plants in my garden that will provide some winter color. I have learned that it is best to plant them in a location where we can see them from our windows. Planting them in the back garden is a waste since we are not often there in winter to see them.

Sarcococca - Copy
Sweetbox is an appealing evergreen with very fragrant winter flowers.

In addition to looking for winter color, this is also a good time of year to walk through the garden and see if there are ‘pockets’ around plants where the water has settled and is not draining. In these areas, I like to add Black Gold Soil Natural and Organic Soil Builder to increase aeration and drainage and add needed organic matter for the coming year. A phrase that I often hear is “more plants die from winter wet than winter cold.” This is certainly the case for many garden plants, such as salvias.

Evergreens

For winter color, a new plant (to me) that can provide golden chartreuse color to the garden is Thuja orientalis ‘Franky Boy’. We often think of Thuja as being large plants, but this one just grows 4-6 inches per year and will only reach about 3 feet in ten years, so it can be used in a garden border. It has thread-like foliage and an upright ball shape. For the opposite color extreme, a silver evergreen conifer is Abies koreana ‘Silberlocke’. This outstanding, slow-growing plant has curved green needles that show silvery-white undersides. I have had one in a pot for several years, and it looks great at any time of the year.

Abies 'Silberlocke'
Abies ‘Silberlocke’ is a lovely winter evergreen with silvery needles.

Sweet Box

I should not overlook some of the shrubs that are already in bloom in the January garden. Sweet box (Sarcococca ruscifolia) is one. It is a very easy-to-grow small evergreen shrub that produces a small, sweetly fragrant, creamy white flower in winter that perfume the area around it. I’ve often had visitors walk past my plants and all of a sudden will detect the fragrance and not know where it is coming from. Sweet Box likes some shade from the hot afternoon summer sun and likes organic-rich soil, so be sure to add Black Gold Garden Compost at planting time.

Wintersweet

Recent snow and ice provided opportunities for gardeners to take some unique photos. Oregon State Community Horticulturist, Neil Bell, sent me this photo of his wintersweet (Chimonanthus praecox) with its flowers encased in ice. He reported that the ice did not seem to bother them, and once it had melted, the flowers went back to scenting the garden. Wintersweet can grow to 10-12 feet and produces winter flowers on leafless branches. If space considerations are an issue, it can easily be pruned to a smaller stature.

Thuja orientalis Franky Boy
The golden-green Thuja orientalis ‘Franky Boy’ is a new dwarf conifer for my garden.

So, while at first glance we might think the winter garden is bleak, it does not have to be. Check out your local garden centers now for plants showing bloom and/or color. I am noticing that many local garden centers are grouping slow-growing conifers together to show the array of colors available. Gardening in the Pacific Northwest is a year-round adventure!