- Deciduous shrub
- Zones vary by type
- Full sun
- Regular water
Native to eastern North America, blueberries thrive in soil conditions that suit rhododendrons and azaleas, to which they are related. Plants require sun and moist, well-drained acid soil (pH 4.5-5.5). Where soil pH isn’t acidic enough, create proper conditions by adding sulphur and sphagnum peat moss; or grow plants in containers filled with acidic potting mix.
Most blueberries grown for fruit are also handsome plants suitable for hedges or shrub borders. Dark green or blue-green leaves to 3 in. long change to red, orange, or yellow combinations in autumn. Spring flowers are small, white or pinkish, urn shaped. Summer fruit is very decorative. Set plants about 3 ft. apart for an informal hedge; as individual shrubs, space them at least 4-5 ft. apart.
Blueberries are available bare-root or in containers. Plant in late winter to early spring. Position crown so that it is ½ in. above the ground. Grow at least two kinds for better pollination, resulting in larger berries and bigger yields per plant. For a long harvest season, choose types that ripen at different times. Blueberries have fine roots near the soil surface; keep them moist but don’t subject them to standing water. A 4- to 6-in.-thick mulch of pine straw, ground bark, or the like will protect roots and help preserve soil moisture. Don’t cultivate around the plants.
Plants often produce so many fruit buds that berries are undersized and growth of plants slows down. Pruning will prevent overbearing. Keep first-year plants from bearing by stripping off flowers; on older plants, cut back ends of twigs until fruit buds are widely spaced. Or simply remove some of oldest branches each year. Also get rid of all weak shoots. Netting will keep birds from getting the berries before you do.
In home gardens, blueberries don’t usually suffer from serious pests or diseases requiring regular controls. One exception is blueberry stem blight, caused by the fungus Botryosphaeria dothidea, which can be a severe problem for all blueberries in the Southeast. The disease enters plants through wounds in the bark and causes rapid death of some or many stems, which drop their leaves and turn dark brown to black. Young plants may be killed outright. There is no chemical control; prompt pruning of infected stems back to healthy wood is the best way to limit the disease. Stop fertilizing after July to reduce succulent new growth, which is more vulnerable to infection. Avoid the selections ‘Bluechip’ and ‘Bounty’, which are more susceptible.