Vaccinium 'Duke'

Tried and Trouble-free Recommended by 2 Professionals
Common Name: highbush blueberry
Type: Deciduous shrub
Family: Ericaceae
Zone: 5 to 8
Height: 5.00 to 7.00 feet
Spread: 5.00 to 7.00 feet
Bloom Time: May
Bloom Description: White
Sun: Full sun to part shade
Water: Medium to wet
Maintenance: Medium
Suggested Use: Hedge
Flower: Showy
Leaf: Good Fall
Attracts: Birds, Butterflies
Fruit: Showy, Edible

Culture

Best grown in acidic (pH of 4.8 to 5.2), peaty, organically rich, medium to wet, well-drained soils in full sun to part shade. Shallow, fibrous roots need constant moisture and good drainage. Plants appreciate a good organic mulch. Although blueberries are self-fertile, cross-pollination produces the best fruit crop (larger berries and larger yields). Therefore, it is best to plant more than one variety that will bloom at the same time. In addition, blueberry season can be extended by planting early, mid-season and late varieties which will collectively ripen from early June to the end of the summer (St. Louis area). Best to remove flowers from plants in the year of planting and in the following year so as to prevent fruit set and to encourage new vegetative growth. Prune as needed in late winter beginning in the third year after planting.

Noteworthy Characteristics

Vaccinium is a genus of about 450 species. Some species and hybrids, including blueberries, cranberries and huckleberries are grown primarily for their fruit.

Genus name comes from an ancient Latin name apparently derived from a prehistoric Mediterranean language.

‘Duke’ is a highbush cultivar that typically grows 5-7’ tall. It flowers late but fruits early, often producing an abundant crop of blueberries. Waxy, bell-shaped, white flowers appear in May. Flowers are followed by medium to large, light blue blueberries which ripen in early season (early to mid June). Berries have a mildly sweet flavor. Ovate, dark green leaves (to 3.5” long) turn attractive shades of yellow and orange in fall.

Problems

No serious insect or disease problems. Birds love the fruit, so plants may need to be covered with netting as the fruit begins to ripen in order to protect the crop. Chlorosis (yellowing of leaves) may occur in high pH soils. Potential but infrequent disease problems include stem blight, root rot, anthracnose, cane cankers, mildew and botrytis. Blueberry maggot and cherry fruit worm may attack the fruit. Mummy berry is a fungal disease that causes the berries to shrivel and drop. Disease problems are sometimes of lesser concern when plants are being primarily grown as ornamentals.

Garden Uses

Useful for ornamental purposes (flowers, fruit, quality summer foliage and fall color) as well as for fruit production (blueberries). It is effective in shrub borders or as part of less formal shrub plantings in areas such as native plant gardens or open woodlands. Particularly effective in conjunction with rhododendrons and azaleas which share similar acidic soil requirements. Also makes an excellent low hedge with the added benefits of fruit which can be harvested or left for the birds.