Black Currant Berry Trees

Identification

• Black currant berry shrubs usually grow around 6 feet tall depending on the cultivar. They have stout, woody, spineless branches, hairy leaf stalks, and three- to five-lobe, heart-shape leaves with serrated margins. The leaves range in size from 2 to 4 inches across. The flowers, which grow in drooping clusters of between four and 10 blossoms, are purplish-green inside and greenish-white on the outer surface, with a hairy, bell form and five stamens. Clusters of round, juicy black berries replace the flowers.

Cultivars

• Several different cultivated varieties, or cultivars, are commercially available. Ribes nigrum "Consort" yields small or medium currants, while "Titiana" produces a high volume of good quality, large fruit. Ribes nigrum "Ben Sarek" is popular among home gardeners. "Ben Sarek" plants grow to around 3 feet high with a compact form and produce large numbers of high-quality black currants. All three species have demonstrated a high resistance to white pine blister rust infections, although the "Consort" variety is susceptible to several other diseases such as leaf spot.

Growing Requirements

• Black currant shrubs grow best in well-drained, cool, moist, sandy loam soil and full sunlight, although they can tolerate partial shade. They prefer a pH level around 6.5 and require large amounts of nitrogen. Add manure to the soil before planting black currant shrubs. Prune out damaged, diseased or broken branches during the winter or early spring while the plants are still dormant and add mulch around the plants to maintain a cool soil temperature and suppress weed growth. They usually begin bearing fruit during their second or third year.

Liabilities

• White pine blister rust is one of the most damaging diseases of white pines in North America. The Cronartium ribicola fungus requires a member of the Ribes family such as gooseberry or currant to complete the disease cycle, so avoid planting black currant shrubs in areas where white pines are cultivated. Several other diseases and pests also attack black currant shrubs. Leaf spot infections such as anthracnose create brown spots on the foliage, while powdery mildew infections attack the branches, shoots and leaves, forming powdery white areas of fungus on the foliage. Sawfly larvae, referred to as currant stem girdlers, damage new shoots, while San Jose scale insects and currant aphids drain sap from the stems and foliage.