Viburnum utile has made its way around the world from China due to the fact that it isn’t specific when it comes to soil types and is heat tolerant. Its glossy leaves can reach 1.2 to 2.5 m tall and its branches are sometimes leggy. Its flowers are often described as snowballs.
I. Appearance and Characteristics
Viburnum utile, the service viburnum, is a species of flowering plant in the family Viburnaceae, native to central and southern China. A leggy evergreen shrub reaching 4 to 8 ft (1.2 to 2.4 m), it is rarely found in commerce. Instead, its chief utility has been as a parent to viburnum hybrids, including Viburnum × burkwoodii (with V. carlesii) and Viburnum × pragense (with V. rhytidophyllum). The V. × burkwoodii cultivars ‘Mohawk’ and ‘Park Farm Hybrid’, and the V. × pragense cultivar ‘Pragense’ have all gained the Royal Horticultural Society’s Award of Garden Merit.
II. How to Grow and Care
Sunlight
Service viburnum in cold environment loves to grow in full sun on slopes and edging rocks in its natural habitat. Varieties adaptable to warmer climates grow well in full sun to medium shade; long exposure to strong light should be avoided. They can be shaded by buildings or big trees. A certain amount of scattered light is needed in the flowering phase to ensure enhanced and continuous flowering in warmer climates, but overall, plants in this genus perform well receiving 5-6 hours of continuous sunlight in a day.
Temperature
The optimum growth temperature range is between 5 to 27 ℃. It has good cold resistance; some native North American species can tolerate temperatures below -25 ℃. Its growth is poor at temperatures above 29 ℃, so it cannot survive in tropical summers. Germination requires 20 consecutive days of seed exposure to 24 ℃.
Service viburnum needs occasional watering during hot and dry conditions. The average plant during its first 2 years of growth needs 1.2 to 1.5 cm water bi-weekly. Once established, it doesn’t need much watering.
Watering
Service viburnum is a plant that thrives in environments with moderate humidity. It has developed a relative balance in its water needs, neither craving excess moisture nor being overly drought-tolerant. This species requires watering once every 1-2 weeks to maintain optimal health. Being an evergreen plant, service viburnum retains its leaves throughout the year, thus requiring consistent water supply even during non-growing seasons.
Soil
Service viburnum likes fertile, soft, slightly acidic soil with good drainage. It likes moist soil but does not grow well in waterlogged soils. It can grow in moderately fertile, fully drained soils that keep minimum moisture, but cannot withstand poor soil. The optimum soil pH range is 5.5-6.6. It can tolerate acidic media and drought with good air circulation in the root zone, which is made possible by the addition of peat moss or coco coir to the media. The best potting soil would be to mix 1 part of fully decomposed organic matter into 2 parts of garden soil.
Fertilizing
Applying organic fertilizer in a planned and reasonable way can improve soil structure, increase soil organic matter content, and increase soil fertility. Fertilization is indispensable for growth, and fertile soil promotes the overall growth of the plants. When transplanting, apply an adequate amount of basal fertilizer, and apply fertilizer every 2 weeks during the flourishing growth stage. Fertilizer should be applied when the weather is clear and the soil is dry.
To ensure normal growth, fertilization should be carried out before the dormant period or after the leaves are preparing to fall, and before the soil freezes. Don’t fertilize the soft cuttings until they start sprouting. For transplants, fertilizer rich in nitrogen is necessary to initiate vegetative growth. In the later flowering stages, it can be replaced with high phosphorus fertilizer.
Planting Instructions
The best time for transplanting is in late spring or early summer. It is best to plant them all on the same day. Take care that roots aren’t exposed to direct light and are buried deep into the planting pit.
Before planting, you need to know the height of a fully mature plant for the variety that you are growing. Generally, the role of thumb is to divide the height of the plant by 2 to determine space. For example, if the selected variety is predicted to grow 4 m tall at full maturity, space the plants 2 m apart. Dig a pit measuring 30 cm deep and 30 cm wide.
Pruning
Light pruning to remove dead or dried branches or injured parts of the plant can be done at any time of the year. Service viburnum doesn’t need severe pruning; how much depends on the type of variety and purpose of growing.
Pruning to shape and beautify can be done in the late winter or early spring. When growing for borders and hedges, cut only 1/3 of the branches if they are severely intermingled. In other cases, pruning can be initiated right after flowering but before the setting of fruit. To avoid frost damage, don’t prune during frost or severe cold.
Propagation
Planting service viburnum from seeds is not recommended. It can take 12-18 months. Soft cutting is one of the best options to grow the plant. Be sure each soft cutting contains 2 nodes for both underground and aboveground parts. Mix 1/3 fully decomposed organic matter with 2/3 dugout soil. Place the soft cuttings into a hole and press the soil gently to keep its level at the garden level. Immediate watering will make a suitable watering pit after the soil has settled.
III. Uses and Benefits
They are used on edges, in light undergrowth, as isolated specimens, in shrubby groups and in pots for patios and terraces.
