Viburnum carlesii aka Koreanspice Viburnum

Viburnum carlesii, or Koreanspice viburnum, is a deciduous shrub. It belongs to the Viburnaceae family and grows in temperate regions. Its native range includes Korea, Japan, and southeastern China. Several woody stems form a dense, rounded crown. Stiff branches grow upward, then spread outward. Most garden plants reach 4–6 feet [1.2–1.8 metres] tall and wide. Larger plants can approach 8 feet [2.4 metres]. RHS gives an upper size of 8.2 feet [2.5 metres]. Growth is slow, with full size taking 10–20 years.

The gray bark develops cracks as the stems age. Fine hairs cover young stems and leaf undersides. Leaves grow in opposite pairs along the branches. Each simple leaf has an oval shape and toothed edges. New leaves can show copper tones before turning dull green. Some leaves have a gray-green cast rather than dark green. Fall leaves may turn red or burgundy. This color varies, so gardeners cannot count on it yearly. Soft, exposed leaf buds differ from the clustered flower buds.

Pink or reddish buds open into small white, tubular flowers. Dense cymes form rounded clusters at the branch tips. Their strong scent makes flowers the shrub's main garden feature. Bloom comes in spring, with timing varying by region. Connecticut reports late April; Chicago lists May through June. In Chicago, flowers may last for about two weeks. Small, oval drupes follow the blooms. They start red and turn black or blue-black when ripe. Fruit ripens toward late summer and fall, and birds eat it. The shrub also draws butterflies.

Grow it in sun or partial shade with moist soil. Good drainage matters, and humus-rich soil suits it well. It accepts clay, loam, sand, and chalk. Slightly acidic soil suits it, though RHS lists wider pH tolerance. Sources place it in USDA zones 4–8 and UK rating H6. Some sources limit zone 4 use to warmer sites. Use it in borders, hedges, groups, or foundation plantings. Paths and doors offer places to enjoy its scent. Prune after flowering; grafted rootstocks may send up suckers.

Care needs are low, but pests and diseases can occur. Aphids, viburnum beetles, crown borers, and nematodes may cause trouble. Leaf spot, powdery mildew, and gray mould can affect plants. Phytophthora and honey fungus may also damage them. RHS warns that people and pets must not eat the fruit. It also calls for gloves and protective gear when handling.