Winterthur Smooth Witherod Viburnum (Viburnum nudum ‘Winterthur’) is an outstanding deciduous flowering shrub prized for its glossy dark green foliage, abundant creamy-white spring flowers, colorful ornamental berries, and spectacular burgundy-red fall color. This attractive selection of native Smooth Witherod Viburnum offers exceptional three-season interest while providing valuable food and habitat for birds and beneficial wildlife.
In late spring to early summer, Winterthur produces an abundance of flat-topped clusters of delicate creamy-white flowers that attract bees, butterflies, and other pollinators. When planted near a compatible, genetically different Smooth Witherod Viburnum, the flowers develop into beautiful clusters of ornamental berries that transition from green to pink and eventually deep blue to purplish-black. Multiple berry colors may appear on the same plant, creating a particularly attractive late-summer and fall display.
Throughout the growing season, Winterthur maintains lustrous, dark green foliage and a naturally rounded, upright growth habit. As temperatures cool in autumn, the leaves develop rich shades of burgundy, wine-red, and reddish-purple, creating a dramatic seasonal display.
Winterthur is particularly well suited for traditional landscapes, estate-style gardens, native plantings, rain gardens, and woodland borders. Its adaptability to moist soils makes it an excellent choice for low-lying landscape areas, pond borders, and locations where many traditional ornamental shrubs struggle. Its colorful berries and attractive fall foliage also make it a valuable addition to wildlife-friendly landscapes.
More About Winterthur Smooth Witherod Viburnum
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Deciduous Flowering Shrub
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North American Native Species Cultivar
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Upright, Rounded Growth Habit
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Creamy-White Spring Flowers
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Ornamental Pink, Blue, and Purple-Black Berries
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Glossy Dark Green Foliage
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Brilliant Burgundy-Red Fall Color
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Bird Friendly
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Butterfly and Pollinator Friendly
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Wildlife Habitat Value
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Moist Soil Tolerant
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Wet Soil Tolerant
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Rain Garden Suitable
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Adaptable to Clay Soils
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Low Maintenance
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Excellent for Mixed Shrub Borders
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Foundation Planting, Informal Hedge, Woodland Edge, Rain Garden
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Outstanding Spring, Summer, and Fall Interest
Height: 5–8 Feet
Spread: 5–8 Feet
Hardiness Zone: 5–9
Characteristics
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Sun Exposure: Full Sun to Partial Shade
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Season of Interest: Spring, Summer, Fall
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Soil Moisture: Average to Wet; Prefers Moist, Acidic Soil
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Attributes: Native Species Cultivar, Flowering, Berry Producing with Cross-Pollination, Bird Friendly, Pollinator Friendly, Wet Soil Tolerant
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Foliage Color: Glossy Dark Green; Burgundy-Red to Purple in Fall
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Flower Color: Creamy White
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Berry Color: Pink, Blue, Purplish-Black
Care & Maintenance Tips
Planting:
Plant in full sun to partial shade in moist, organically rich soil. Winterthur prefers slightly acidic conditions and adapts well to locations with consistently moist or occasionally wet soil. It is particularly suitable for rain gardens, pond borders, woodland edges, and low-lying landscape areas.
For the best berry production, plant near a different, compatible Smooth Witherod Viburnum cultivar with overlapping flowering times. Brandywine™ Viburnum is an excellent companion for cross-pollination.
Watering:
Water regularly during the first growing season to establish a strong root system. Once established, Winterthur performs best with consistent soil moisture and tolerates wetter conditions than many common landscape shrubs. Provide supplemental watering during extended periods of drought, particularly in sunnier locations.
Fertilizing:
Apply a balanced slow-release fertilizer in early spring if needed. Incorporating compost or organic matter can help improve soil quality and moisture retention. Avoid excessive fertilization, which can encourage foliage growth at the expense of flowering.
Pruning:
Winterthur naturally develops an attractive rounded habit and generally requires minimal pruning. Remove dead, damaged, or crossing branches as needed. If shaping is necessary, prune immediately after flowering. Avoid excessive pruning, as removing spent flowers or developing fruit will reduce the ornamental berry display.
Winter Care:
Winterthur is a cold-hardy deciduous shrub that requires little winter protection once established. Apply a layer of organic mulch around the root zone to help retain moisture and moderate soil temperatures, keeping mulch away from the main stems.
Pollination Requirements:
For reliable berry production, plant Winterthur near a genetically different Smooth Witherod Viburnum with overlapping bloom times, such as Brandywine™. Multiple Winterthur plants alone will not provide the cross-pollination needed for the best fruit display.
