Viburnum nudum ‘Winterthur’ (Withe Rod)

Viburnum nudum ‘Winterthur’ (Withe Rod) is a popular cultivar of Viburnum nudum, distinguished by its multi-seasonal appeal. From its spring blooms to its colorful fall foliage and attractive winter berries, this shrub offers year-round interest. It’s also an ecologically friendly choice, providing both nectar for pollinators and fruit for birds. Additionally, Viburnum nudum ‘Winterthur’ is relatively easy to care for, requiring minimal pruning and being largely disease-resistant, making it a low-maintenance option for both novice and expert gardeners alike.

Viburnum nudum ‘Winterthur’: A Must-Have for Your Garden

Native: This particular cultivar, ‘Winterthur,’ is a garden variety, but the species Viburnum nudum is native to the Eastern United States, commonly found in wetlands and along streambanks.

Habit: The ‘Winterthur’ exhibits a dense, compact, and rounded growth habit, making it a suitable choice for foundation plantings or naturalizing in woodland gardens. It can also function as a background plant due to its seasonal features.

Size: This deciduous shrub typically grows to about 5-6 feet (150-180 cm) tall and wide, although it can reach greater dimensions in optimal conditions. Its moderate size makes it versatile for various garden settings.

Flowers: In early to mid-summer, the shrub blooms with creamy-white, flat-topped clusters of flowers that are about 3-5 inches (7-12 cm) across. These blossoms add a delicate touch and stand out against the glossy green leaves.

Berries: Another standout feature of Viburnum nudum ‘Winterthur’ is its showy berries. After the flowering period, the plant produces clusters of small, initially green berries that undergo a stunning transformation as they mature. The berries turn from green to shades of pink, then deepening to blue, and eventually turning to a dark, almost black color. This kaleidoscope of colors often appears on the same cluster, creating a unique and eye-catching display. These berries are not only ornamental but also provide a valuable food source for various species of birds and wildlife, adding another layer of ecological benefit to this already versatile shrub.

Foliage: The foliage of Viburnum nudum ‘Winterthur’ is one of its most compelling features. The leaves are elliptical, up to 4 inches (10 cm) long, and have a glossy, leathery texture. In spring and summer, the leaves are a rich dark green that serves as a beautiful backdrop for its white flowers. As the season progresses into autumn, the foliage undergoes a spectacular transformation, turning shades of deep red to purplish red, adding additional seasonal interest. This vibrant autumn display makes it a standout in the landscape, especially when combined with its colorful berries. The glossy leaves also lend the shrub a refined appearance, even when not in bloom or fruit.

Hardiness: Viburnum nudum ‘Winterthur’ is hardy to USDA Zones 5-9. It is known for its adaptability to various soil conditions, including wet soils, making it ideal for areas that receive abundant rainfall or for planting near water features.

Award: Winner of the Pennsylvania Horticultural Society Gold Medal (Steyer Award) in 1991.

Uses: Because of its compact size and seasonal appeal, it is frequently used in landscape design. Whether used as a standalone specimen or in a mixed border, its varied colors throughout the year make it an excellent choice for year-round interest. It is also suitable for rain gardens due to its tolerance for wet conditions.

Wildlife: The berries of ‘Winterthur’ are a source of nourishment for a variety of birds, including robins and bluebirds. The flowers attract pollinators like bees and butterflies, enhancing the garden’s ecosystem.

Deer and Rabbits: Viburnums are considered to be somewhat deer-resistant but not entirely deer-proof. The same goes for rabbits; while they may not be the first choice for these animals, in conditions of scarcity, they might still browse on the leaves and twigs.

Toxicity: The plant is generally considered non-toxic to humans and pets. However, it is always advisable to keep all ornamental plants out of the reach of young children and pets who might ingest them out of curiosity.

One of the standout benefits of this plant is its multi-seasonal appeal. From its spring blooms to its colorful fall foliage and attractive winter berries, this shrub offers year-round interest. It’s also an ecologically friendly choice, providing both nectar for pollinators and fruit for birds. Additionally, Viburnum nudum ‘Winterthur’ is relatively easy to care for, requiring minimal pruning and being largely disease-resistant, making it a low-maintenance option for both novice and expert gardeners alike.

How to Grow and Care for Viburnum nudum

Growing and caring for Viburnum nudum ‘Winterthur’ requires some basic horticultural practices to ensure the plant thrives in your garden. Here’s a simple guide to help you:

Sunlight:

• It prefers full sun to partial shade. In hotter climates, some afternoon shade may be beneficial.

Soil Conditions:

• This viburnum is adaptable to a range of soil types but prefers average, medium to wet, well-drained soils. You can add organic matter to improve drainage and fertility.

Planting:

• Best planted in the spring or fall, dig a hole twice the width of the root ball and as deep.
• Set the plant in the hole, fill it with soil, and water thoroughly.

Watering:

• Water regularly during the first growing season to establish a deep, extensive root system. Once established, it becomes more drought-tolerant but will appreciate consistent moisture, especially in dry conditions.

Fertilization:

• A balanced, slow-release fertilizer applied in early spring should suffice for the growing season.

Pruning:

• Generally low-maintenance, you can prune to shape immediately after flowering. This plant blooms on old wood, so avoid heavy pruning in late summer or fall as it will remove next year’s flowers.

Pests and Diseases:

• Viburnums are generally resistant to many pests and diseases. However, keep an eye out for aphids, thrips, and spider mites. If you notice any infestation, treat it promptly with an appropriate insecticide.

How to Propagate

Propagation of Viburnum nudum ‘Winterthur’ can be achieved through a few different methods, but the most commonly used ones are softwood cuttings and layering. Here’s how to propagate using these techniques:

Softwood Cuttings:

• Timing: Take softwood cuttings in late spring to early summer when the new growth is still somewhat pliable but not too soft.
• Cutting: Cut a 4-6 inch (10-15 cm) piece from the tip of a healthy branch. Make sure the cutting has at least two sets of leaves.
• Preparation: Remove the leaves from the lower half of the cutting. Optionally, you can dip the cut end into a rooting hormone to encourage faster root development.
• Planting: Stick the cut end into a pot filled with a well-draining soil mix, such as half perlite and half peat moss.
• Rooting: Keep the soil moist and place the cutting in a location with high humidity and indirect light.
• Transplanting: Once the cutting has rooted, usually within 4-8 weeks, you can transplant it into a larger pot or directly into the ground.

Layering:

• Timing: Layering is best done in late winter or early spring.
• Preparation: Choose a healthy, lower branch and bend it down to touch the soil surface.
• Contact: Where the branch touches the soil, make a small 1-inch incision on the underside of the branch.
• Anchoring: Use a metal pin or stone to keep the incised part of the branch in contact with the soil.
• Rooting: Over the growing season, the incised part should develop roots.
• Sever and Transplant: Once roots have formed, sever the new plant from the parent and transplant it to a new location.