Vaccinium - Bearberry, Bilberry, Blueberry, Burren Myrtle, Cowberry, Cranberry, Craneberry, Crowberry, Dyeberry, Farkleberry, Huckleberry, Hurtleberry, Lingberry, Lingonberry, Partridgeberry, Sparkleberry, Whinberry, Whortleberry, Wineberry

(Vaccin'ium)

DESCRIPTION:This group consists of about 450 species of evergreen and deciduous shrubs found over the cooler areas of the Northern Hemisphere and in the mountains of South America. Some kinds are grown for the beauty of their fall leaves and some for their attractive flowers and deliciously edible fruits. Many different names have been given to the numerous varieties that produce edible fruits, such as Blueberry, Bilberry, Cowberry, Cranberry, Crowberry; Farkleberry, Lingonberry, Partridgeberry, Huckleberry (not the true Huckleberry, which is Gaylussacia), Whortleberry, and Sparkleberry to mention a few. For others, check in the varieties section underneath the Blueberry varieties. The other varieties need basically the same care and soil pH as Blueberries.

Blueberry: Blueberries are one of the most popular of the berries. They can be eaten fresh or baked into pies, muffins, and other treats. They can be dried, canned, or froze for use throughout the winter. These vigorous growing plants, which don't require severe pruning, are quite resistant to pests and diseases. The only thing these plants are very particular about is the soil's pH, which should be around 4.0 to 5.5. If your soil's pH is too high, it can be amended with organic materials such as composted leaves, pine or hemlock needles. Oak, beech, and chestnut leaves, as well as hardwood and softwood sawdust, are also excellent choices to lower the pH. Blueberries are handsome landscape plants with their bell-shaped, waxy white flowers in the spring and vivid, autumn foliage. They can be pruned to have a tree-shape or be a low hedge. There are three main types of Blueberries: lowbush, highbush, and rabbiteye. A variety of hybrids have been developed that can survive the bitter cold winters of the North and withstand the extreme heat of the South. There are high-growing varieties, which can make a pleasant, natural fence between properties and low-growing varieties for people with limited spaces. Blueberries are self-pollinating, but if you cross-pollinate with another plant, the fruit will be larger, ripen earlier, and have fewer seeds. Blueberries begin to ripen in early summer and continue over a period of several weeks. There are early, mid-season, and late-fruiting varieties that can be planted together to provide a long harvest. When this is done, remember to plant pollinators that bloom at the same time. Highbush Blueberry: V. corymbosum is the botanical name for this variety. These plants produce an abundance of large, sweet fruits. Highbush Blueberries are found in wetlands and drier upland wooded slopes from Nova Scotia west to Wisconsin, south to Georgia and Alabama. Many cultivars thrive as far north as Zone 3. Most Highbush Blueberries don't do as well in the South, because most require about 700 chill hours to break dormancy in the spring; however, there are a couple that can be grown quite far South. In the wild, these erect-growing bushes can reach a height ranging from 5 to 15 feet; in the garden, their height ranges from 6 to 12 feet. Lowbush Blueberry: These dwarf bushes produce tons of small berries with intense flavor. A single plant usually produces 1 to 2 pints of berries. These Blueberries are very cold hardy, surviving in the wild as far north as Arctic North America. These Blueberries only reach a height of 1 or 2 feet. Lowbush Blueberries include the low sweet Blueberry (V. angustifolium), which is found from the Arctic to Minnesota and the mountains of New York and New Hampshire, and the sour-tasting velvet-leaf Blueberry (V. myrtilloides), which is found wild throughout New England and west through zone 2. In the wild, these plants spread by underground rhizomes and create vast colonies called "Blueberry barrens". These wild colonies are harvested commercially and are used for freezing and canning and to make jams and jellies. Every few years in late winter when the ground is frozen, the bushes are burned off in order to remove the weeds that will compete with the plants. The bushes will produce fruits the following year. These cold-hardy bushes cannot tolerate too much heat; therefore, their limit is about zone 7. Rabbiteye Blueberry: These Blueberries (V. ashei) are excellent for growing in mild-winter regions including the Atlantic coast and coastal Alaska. These tall (from 10 to 25 feet), erect- and vigorous-growing bushes flourish where summers are hot and humid and they tolerate dry periods better than other Blueberries. However, they are only cold hardy to zone 6 or 7. Plants that are well mulched may survive a dip in temperature as low as -20º F though the branches may die back to the ground. They also will flourish at slightly higher pH levels than Highbush types. Because of their tall height, many people prune them to keep them within reach.

Cranberry: The botanical name for the Cranberry (also known as Bearberry and Craneberry, named after the animals that love to feed on these berries) is V. macrocarpa. This prostrate, evergreen shrublet has thin, wiry, creeping stems and small, oval leaves. The small, pendant, flowers are pink with yellow anthers and are borne in clusters in the summer. The round, red fruits are edible, but tart. They can be dried and eaten like raisins, they can be used to make cranberry juice, or cooked to make jelly. The Cranberry needs moist, peaty boggy soil with a pH of 4.0 to 6.1.

Alpine Cranberry; Cowberry; Lingonberry; Lingberry; Lingon; Lingen; Moss Cranberry; Mountain Cranberry; Partridgeberry; Red Whortleberry; Rock Cranberry: V. vitis-idaea is a hardy, low-growing, evergreen shrub with many common names. It grows up to a foot high with small, glossy dark green, leathery leaves and pendant spikes of pinkish-red flowers. The blossoms are followed by sour, edible, red fruits. These can be used to make juice, sauce, preserves, jelly, candy, wine, liqueurs and a variety of other things. Crowberry: V. vitis-idaea variety 'Koralle' is a form of the mountain Cranberry, sometimes called Crowberry. This dwarf, creeping, evergreen shrub has small, glossy, dark green leaves and white tinged with pink, bell-shaped flowers. They are produced in short clusters from early to late summer and are followed by large, red berries.

POTTING: As mentioned in the description above, Blueberries require a pH of 4.0 to 5.5. Rabbiteyes can tolerate a slightly higher pH than this. (If Azaleas and Rhododendrons flourish in your garden, Blueberries will, too.) It is beneficial to test your soil's pH level. If the soil is over 6.2 on the pH scale, you should grow your Blueberries on mounded beds of amended soil or in containers. If your soil is in the 5.3 to 6.0 range, amending the soil will usually work. Mixing an acidic material into the soil will lower its pH. Peat moss was normally used, but taking this material destroys the ecology of peat bogs. It is best to use composted leaves, pine or hemlock needles, oak, beech, and chestnut leaves and/or bark, hardwood and softwood sawdust, or bald-cypress leaves and composted cypress bark. Whatever your choice is, it should be chopped, shredded, or chipped very small before mixing it with the soil. If the soil is amended too heavily causing a nitrogen deficiency, your plants will grow slowly and the leaves will turn yellow and then red. To counteract this deficiency, add cottonseed or blood meal, dry manure, or packaged high-nitrogen fertilizers. Make sure to check the moisture in amended soil. If the peat, sawdust, or other finely ground materials dry out, they will repel rainwater instead of soaking it up. Blueberries have shallow roots; therefore, when amending the soil, you need not dig too deeply - about 8 inches is sufficient. Your soil should end up light, loose, crumbly, and moisture retentive (but well drained), like the sandy, humusy, woodland soil in which they naturally grow. In clay soil, you will need to replace about half the soil with the organic materials; in loam, about a quarter to a third will do. These improvements should last the lifetime of the plant as long as you add a 4- to 5-inch thick mulch of acidic materials annually, replenishing it as it decomposes. The mulch also keeps the soil cool and moist. Blueberries should be grown in a sunny location. Avoid planting them in "frost pockets", where cold air settles, such as at the bottom of a hill or other low-lying area. Blueberries are sold as two- or three-year-old plants, ordinarily in containers. In cold-winter climates, plant in early spring; in mild-winter climates, plant in autumn or early winter. When transplanting them, do not let the roots freeze or dry out and don't expose them to sunlight, which will kill the small, fibrous roots. Protect the bare roots with a damp, lightproof covering. Highbush varieties should be planted 3 feet apart if a formal hedge is desired. If you want a natural setting, plant them 4 to 6 feet apart. Rabbiteye varieties should be grown up to 8 feet apart, or closer for a hedge. Lowbush varieties can be grown 2 to 3 feet apart or 1 to 2 feet apart for a ground cover. Since Blueberries have shallow roots that can easily be damaged by drought, tilling, hoeing, and even handpicking weeds, it is wise to use mulch (as mentioned before) to prevent weeds and retain moisture. When checking to make sure the soil is moist, push away a bit of mulch and stick your finger into the soil.

Container-growing Blueberries: Blueberries can easily be grown in containers if your soil pH is beyond simple repair or if space is limited. They will flourish if kept well watered and fed regularly with high-nitrogen fertilizer. A pair of wooden half-barrels, one plant in each, make suitable containers for Blueberries. Two different cultivars ensure cross-pollination. Fill the containers with an acid soil mix to within 6 to 8 inches of the rim, so that you have enough room to add a thick layer of moisture-retentive mulch. If you plant in plastic tubs, it's a good idea to add a few heavy rocks or bricks so it won't tip over in the wind. A good soil mix for Blueberries is made by combining two parts garden soil, one part compost, two parts composted chopped leaves or peat, and two parts coarse builders sand. Soil-less mixes, such as three parts sand, three parts peat moss or sawdust, and two parts composted chopped leaves, are also good to plant Blueberries in, except you'll have to fertilize during the growing season to keep healthy plants. If you garden in a cold-winter climate, bring the containers into an unheated garage or porch for the winter. Mulch the roots with a thick layer of leaves and wrap the plant in burlap for extra protection in extreme temperatures. Be sure to water them during the winter months whenever needed; don't let the soil become bone-dry.

Fertilizer: If your soil needed no amendments to correct the pH, each spring, the mulch around each plant should be pulled back and 1/2 to 1lb of high-nitrogen fertilizer, such as dry manure, cottonseed or soybean meal, or a high-nitrogen packaged organic fertilizer, should be applied. Fertilizer formulated for Rhododendrons and Azaleas can be used for Blueberries, although a little less fertilizer than the recommended amount should be used. Keep an eye on the plants for signs of nitrogen deficiency. If the foliage turns yellow and then red, when they should be green, a nitrogen deficiency is probably the cause. Correct this immediately by adding a high-nitrogen liquid fertilizer along with a fast-acting foliar spray to the plants showing stress.

Pruning: Blueberries are easily maintained as they naturally grow in a neat shape. Highbush Blueberries grow erect to slightly spreading, with the several stems producing side branches almost to the ground. Lowbush Blueberries are short and spreading, with branches almost to the ground. This type doesn't need to be pruned, though you can thin out the oldest, most unproductive branches. Rabbiteye Blueberries are more bare-legged, with the stems branching only near the tops. Blueberries will be productive for years without ever being pruned, but for convenient harvesting, it is beneficial. For the first two or three years after planting, they will not need to be pruned at all. Once pruning is necessary, it should be done in late winter. Blueberries bear fruit on year-old and older branches. If you cut back too much, you won't have much of a crop. Once the plants are established in your garden, you can begin pruning to control the height of the taller varieties. Rabbiteyes should especially have their young stems cut back to encourage low branching. When the bush is producing abundantly and the plant seems crowded with branches, you can open the center for the plant's health and better access to the berries. Weak or unproductive branches should be removed first. Check for fruit buds to decide how valuable an older, thicker branch is. The berries will be larger when there are fewer of them. Fruit buds are fat and round and grow near the branch tips; leaf buds are smaller and more pointed and are found farther down the stems. Some people selectively prune the fruit-bearing branch tips in order to reduce the size of the crop and thus allow more energy to go into the production of larger berries. Sometimes, a harsh winter will kill off some or even all of a Blueberry's branches; cut off these damaged branches at an outward-facing node where healthy wood begins. As Blueberries age, the canes become less productive and their tips twiggy. Cut back the twiggy ends of the older branches and thin out six-year-old and older canes once in a while to make room for younger, more productive canes.

Harvest: Most Blueberries begin to produce fruit at age three, which is the first year in your garden if you planted 3-year-old bushes, and can continue to bear for up to 40 years. Depending on the type and variety of your plants, and on your growing area, Blueberries ripen from mid- to late summer over a period of two weeks or longer. The berries don't ripen all at one time. The "Bluecrop" season lasts a month. Turning blue is a sign of ripening, not a sign of ripeness. Most Blueberries turn blue one to two weeks before they're ready to pick. Ripe berries will twist off the stems easily. A taste test is another way to tell if harvest time has arrived.

Pests & Diseases: Home gardeners have little trouble from pests. Two types of insect larvae, the Cherry fruit worm and the Blueberry maggot, are occasionally troublesome. Diseases are also rare in the home garden, but can sometimes cause problems in warm, humid areas, such as the South. Mummy berry is a common enough problem that breeders have developed some cultivars that are resistant to it, such as highbush 'Spartan'. Viral diseases that cause a slow decline and death are sometimes seen, but they have no cure. Your county extension agent can tell you about potential virus problems in your area and make suggestions about resistant cultivars. Birds will be your worst enemy when it comes to protecting your crop. Thrushes and other songbirds will be the most problematic. Some people resort to building a permanent cage for their Blueberries, but plastic mesh bird netting works just as well. Drape it over the bush, making sure there are no gaps or openings, and secure it to the base of the canes. If birds reach through the mesh, suspend it on a frame a foot or so above the berries. The berries are also eaten by bears and small mammals. Deer and rabbits browse on the twigs and leaves as well. If animals become especially troublesome, a fence or cage is the best solution.

PROPAGATION: Blueberries are usually propagated from hardwood cuttings, but the process is difficult. It is better to purchase plants from nurseries. Cuttings, 4 to 6 inches long, can be inserted in shallow trays filled with half peat and half sand. This is done in early spring and the cuttings are covered with sash and lath or burlap shade. They must have good ventilation and be carefully watered. They usually form roots by July, but should remain in the trays until the following spring, when they are transferred to a nursery row for a year.

VARIETIES: V. crassifolium (Creeping Blueberry); V. cylindraceum; V. delavayi (Delaway Blueberry); V. floribundum; V. glaucoalbum; V. moupinense; V. nummularia; V. ovatum (Box Blueberry); V. praestans (Cherry Blueberry); V. retusum.

Highbush Blueberries (6'-12' high) - V. corymbosum; Berkeley (Midseason); Bluecrop (Mid); Bluejay (Mid); Blueray (Mid); Cape Fear (Early to Mid); Collins (Mid); Coville (Late); Darrow (Late); Earliblue (Early); Georgiagem (Early); Ivanhoe (Early); Jersey (Late); O'Neal (Early); Patriot (Early to Mid); Sierra (Early to Mid); Spartan (Early). Lowbush Blueberries (1'-2' high; grow well in zones 2-6) - V. angustifolium; V. angustifolium; Augusta; Brunswick; Chignecto; Leucocarpum (bears white fruit); Tophat (this dwarf has fiery red, autumn foliage); Bloodstone (trailing growth-excellent ground cover). The following are crosses between Highbush & Lowbush Blueberries (hardy from zones 3 to7 - except where noted; all ripen in Midseason) - Blue Haven (zones 5-7); Northblue (20"-30" high); Northcountry (18"-24"); Northland (3'-4'); Northsky (10"-18"; dark red, fall leaves). Rabbiteye Blueberries (most need a pollinator, check w/ your supplier) - V. ashei; Beckyblue (Early); Bluebell (Mid); Brightwell (Early to Mid); Brightwell (Early to Mid); Briteblue (Late); Centurion (Late); Choice (Mid to late); Climax (Early); Delite (Late); Garden Blue (Early to Mid); Powder Blue (Late); Premier (Early to Mid); Tifblue (Mid to late).

V. macrocarpon (Cranberry; Bearberry; Craneberry).

V. vitis-idaea (Alpine Cranberry; Cowberry; Lingonberry; Lingberry; Lingon; Lingen; Moss Cranberry; Mountain Cranberry; Partridgeberry; Red Whortleberry; Rock Cranberry); V. vitis-idaea variety 'Koralle' (Crowberry)

V. myrtillus (Bilberry; Burren Myrtle; Dyeberry; Huckleberry (not true Huckleberry); Hurtleberry; Whortleberry; Whinberry; Wineberry).

V. arboreum (Farkleberry; Sparkleberry) shrub or small tree found in the southern United States. It bears numerous, black, many-seeded berries that have a dry and rather astringent pulp.

Go see DICTIONARY OF BOTANICAL NAMES.

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