Edward F. Gilman, Teresa Howe, Ryan W. Klein, Andrew K. Koeser, Deborah R. Hilbert, and Drew C. McLean
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Introduction
Walter's viburnum, in the opinion of some nursery growers, is the very best viburnum for use in central and south Florida. Unfortunately, it is not widely available. It is a shrub or small tree that can grow to a height of about 27 feet. However, there are forms of this plant that are upright, spreading, weeping, or dwarf. It is difficult to determine which form you are buying by simply looking at the plant. The only way to determine the ultimate height and shape of the plant is to know the original source of the plant material. A reputable nursery will know the characteristics of their plants. The evergreen leaves of Walter's viburnum vary from very small to medium sized, glossy, leathery, and dark green. They are also fragrant when crushed. The winter or spring flowers occur in small, convex cymes held at the branch tips before new growth emerges. Flowers can cover the plant with white blooms for about 2 or three weeks. The fruits of this plant are small drupes that turn from red to black during maturation.
Figure 1. Full Form—Viburnum obovatum: Walter's viburnum
General Information
Scientific name: Viburnum obovatum
Pronunciation: vye-BER-num ah-boe-VAY-tum
Common name(s): Walter's viburnum, blackhaw
Family: Adoxaceae
Plant type: tree
USDA hardiness zones: 7 through 10 (Figure 2)
Planting month for zone 7: year round
Planting month for zone 8: year round
Planting month for zone 9: year round
Planting month for zone 10: year round
Origin: native to the southeastern United States
UF/IFAS Invasive Assessment Status: Native
Uses: espalier; superior hedge; recommended for buffer strips around parking lots or for median strip plantings in the highway; screen; border; attracts butterflies; residential street tree; small parking lot islands (< 100 square feet in size); medium-sized parking lot islands (100-200 square feet in size); large parking lot islands (> 200 square feet in size)
Figure 2. Shaded area represents potential planting range.
Description
Height: 6 to 27 feet
Spread: 6 to 10 feet
Plant habit: oval
Plant density: dense
Growth rate: moderate
Texture: fine
Foliage
Leaf arrangement: opposite/subopposite
Leaf type: simple
Leaf margin: revolute; serrate
Leaf shape: broadly obovate to oblanceolate
Leaf venation: pinnate
Leaf type and persistence: evergreen
Leaf blade length: 1 to 2 inches
Leaf color: dark green and shiny on top, paler green underneath
Pest resistance: long-term health usually not affected by pests
Use and Management
Walter's viburnum may be utilized in the landscape as a fine-textured, clipped hedge or tall screen. Small leaves make it a great candidate for shearing into a topiary, espalier or formal hedge. Older specimens can be trained into small trees with several trunks. Nurseries can also train young plants to grow in this manner.
Walter's viburnum will grow well in a site that receives full sun or shade. It is native to acidic wetland forests that are frequently inundated for a period of time during the year, but it tolerates a broad range of growing conditions including moderate drought.
Pests and Diseases
No pests or diseases are of major concern.
Reference
Koeser, A.K., Friedman, M.H., Hasing, G., Finley, H., Schelb, J. 2017. Trees: South Florida and the Keys. Gainesville: University of Florida Institute of Food and Agricultural Sciences.