The blueberry (vaccinium spp.) is a tasty blue fruit found on bushes that have red fall foliage. Blueberry plants are outstanding additions to a landscape. If you want to plant the best blueberry bushes you will need some facts and information to lead you to that goal.
Where and When to Plant Blueberries
Blueberries should be planted in a sunny, breezy location in well-drained, sandy, acid loam with a pH of 4.5-5.5. Have the soil tested before planting to determine pH and what amendments are needed. If possible, grow a green manure cover crop on the site and till it under before planting blueberries.
Plant blueberries in spring in northern zones and in late fall in the South, in holes spaced 6’ apart fo highbush plants, 2’ apart for lowbush, and 3-4’ for dwarf or hedge highbush varieties. *No plant food should be added to the holes. Keep the plants continuously moist before planting them. Carefully spread the roots out and firm the soil around them, then water well. Set bare-root stock at the same depth it was grown in the nursery, then cut the plants back by half to remove buds.
Blueberry Plant Care
Because blueberry roots lack root hairs, they are sensitive to changes in soil moisture. Keep the plants consistently moist. They need 1-2” of good-quality water low in mineral salts each week. Harvested fruits retain their stems if drought stressed. Spread mulch 6-8” deep and 2-4” wide along the row.
Feed plants each year at flowering with acidic compost or plant food for acid-loving plants. Excessive nitrogen causes low yields. Blueberries fruit on 1 year old wood. Pinch off developing fruits until plants are 3-4 years old, to encourage the bush to grow. Blueberries tend to overbear, which wears out the plants in just a few years if left unchecked.
Prune blueberry plants with loppers when they are fully dormant in late winter. Flower buds will be visible on 1 year old wood. Heavy pruning results in earlier ripening, which may be especially desirable in the South, and also yields larger berries. Renewal-prune annually to remove old canes. In the first 2 years of growth, remove weak, diseased, or damaged canes only.
In subsequent years remove weak, diseased, or damaged canes along with some of the oldest canes. Remove excess young canes to encourage the growth of others, and prune to reduce the density of the branches at the tops of plants. Careful selection of canes to prune to reduce the density of the branches at the tops of plants. Careful selection of canes to prune helps to balance the fruit load on the plant in the next season. Each mature plant should have 15-25 canes of varying ages. The canes will decline in productivity after 5-6 years.
Blueberries are ready to pick 2-4 months after flowering, from July to September. Hold a container in one hand and use your other hand to gently loosen berries from the cluster so they drop into the container. Ripening berries turn from green to pinkish red to blue, but not all blue ones are fully ripe. Blueberries are extremely perishable. Store them unwashed in the refrigerator for up to 1 week. Enjoy them fresh out of hand or on cereals and in fruit salads, or cooked in baked goods, jams, and preserves. They also make blueberry wine, a very delicious sweet wine. Rinse and dry berries and freeze them in single layers in plastic for long-term storage. Blueberries can also be dried and stored in airtight containers for up to 3 years.
Blueberry Shrubs Pests and Diseases
Choose cultivars bred for resistance to viruses. Use labeled fungicides according to directions to control phomopsis canker, root rot, mummy berry, and twig blight. Japanese beetles may bother blueberries in the home garden. Keep the ground clean of dropped fruit and vegetative debris to discourage fruit flies and maggots.
Use insecticidal sprays if needed to control them and fruit worms, curculios, leafhoppers, scale, and borers, but avoid spraying when plants are in bloom to protect beneficial insect pollinators such as bumblebees and southeastern blueberry bees. Use reflective tape or balloons, noisemakers, or netting that covers the plants all the way to the ground to protect ripening fruits from birds.
Best Blueberry Plant Cultivars
The most commonly grown blueberry is the bigbush (Vaccinium corymbosum). It is native to the eastern U.S. and grows to 8’ where soil is highly acid and drains well. Highbush is a hardy blueberry species, requiring 650-850 chilling hours and 160 frost-free days. The buds are hardy to −20 degrees, the stems to −30, and the flowers to 25-30 degrees.
‘Earliblue’, ‘Bluetta’, and ‘Duke’ are early cultivars. ‘Spartan’ is a good choice for regions with late spring frosts. It blooms late but ripens early.
Late-ripening cultivars include ‘Blueray’, a large-fruited variety good for hot climates, and ‘Berkeley’, which grows well in light soils.
‘Olympia’ has good flavor and freezes well.
‘Coville’ is resistant to phomopsis canker.
‘Lateblue’ and ‘Elliott’ are medium-size berries good for eating fresh.
’Sierra’ is an interspecific hybrid of V. constablaei, V. darrowi, v. corymbosum, and V. ashei, that requires 1,000 chilling hours.
Rabbit-eye blueberry (V. ashei) is a highbush species native to the southeastern U.S. that can reach 20” tall. It needs only 250 chilling hours, tolerates hear and dry weather, and is hardy to Zone 7. It ripens later than northern highbush types, and the fruits are not as sweet off the vine but are good for baking. Because it is partially or completely self-sterile, rabbit-eye blueberry requires pollenizers. The fruits are sometimes shiny and frequent harvests promote their ripening.
‘Climax’ is an early cultivar with good flavor.
‘Premier’ is a large, early-to mideastern cultivar with superior flavor.
‘Centurion’ is adapted to heavy soils, blooms late and ripens late. It is a good dessert fruit.
Southern bigbush cultivars include crosses of V. Australe and V. Corymbosum with V. Darrowi as well as crosses of highbush and lowbush called half-high blueberries, bred to create southern-type fruits on plants that are hardy to −20 degrees. They are self-sterile and require pollinizers.
’Sapphire’, ‘Sharpblue’, and ‘Gulf Coast’ are popular in Florida.
‘Northland’ and ’St. Cloud’ are early cultivars; ‘Northblue’ is midseason, and ’Northcountry’ is good for northern Zones. It has the naturally sweet flavor of its lowbush ancestor.
Lowbush blueberry (V. Myrtilloides) is the lowbush species of eastern Canada. The wild plants are managed with sprays and pruning for best yields. Multiple plants are necessary for succesful pollination. They are hardy to −20 degrees and need 1,000 chilling hours below 45 degrees.