Culture
Best grown in acidic (pH of 4 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.
'Northblue' is a cold hardy hybrid blueberry selection that can be grown in Zones 3-7.
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.
The genus name Vaccinium comes from an ancient Latin name apparently derived from a prehistoric Mediterranean language. Its origin and meaning are generally considered to be lost to time.
'Northblue' is a dwarf, hybrid blueberry selection resulting from a cross between Vaccinium corymbosum and V. angustifolium. Mature plants will reach up to 3' tall with an equal spread and an upright to spreading, compact, densely branched habit. The small, white, pendulous, urn-shaped flowers have a pink blush and are followed by sweet and tart, juicy, dark blue berries. This cultivar is self-fertile but may produce larger yields with another individual nearby.
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.
Uses
Useful for ornamental purposes (flowers, fruit, quality summer foliage and fall color) as well as for fruit production (blueberries). Suitable for containers or small spaces.