It really doesn’t matter if you’ve been reading about the great health benefits of blueberries, the unique taste or you just plain have a passion for blueberry muffins, these multi-purpose plants are a must have for gardeners.
Attractive as ornamentals, they progress from a profusion of white or pink blossoms in spring to colorful fall foliage. In addition, their woody stem structure is an aesthetically pleasing addition to the winter landscape. Their delicious berries can be eaten fresh, made into pies and other desserts, frozen, dried or canned for later use.
Depending on variety, the fruiting season extends from early July through September, providing plenty of time for both fresh eating and preserving. It’’s easy to include blueberries in existing landscapes since these acid loving plants have similar growing requirements to rhododendrons, azaleas and heathers.
Blueberries grow best in well-drained soils that are high in organic matter and have a pH between 4.5 and 5.5. If your soil is not naturally suitable for blueberry plant growth, you’ll need to modify it before planting. Blueberry plants are long-lived, so considerable time and expense in preparing the soil can be justified. They are shallow rooted plants, characterized by the lack of root hairs.
Most blueberry roots are found inside the dripline of the bush and in the upper 18 inches of soil. Before planting, incorporate organic matter, such as Douglas-fir sawdust or bark, to improve soil aeration and drainage. If your pH is higher than 5.5 you can acidify the soil by adding finely ground elemental sulfur to the soil before planting. The amount of sulfur needed depends on how much the soil pH needs to be lowered and the soil type.
For example, to lower the pH from 6.5 to 5.4 in a clay loam, you would need to apply 3.5 to 4.5 pounds of sulfur per 100 square feet.
It’’s a good idea to plant more than one cultivar. Although most high-bush blueberry cultivars are self-fertile, cross pollination produces larger berries. Also, if you plant two or more varieties that ripen at different times, you’ll extend the harvest season. If you plan on growing several plants, it’s better to group them than to scatter them around the garden individually. Cultivated blueberry plants usually require six to eight years to reach full production and are 5 to 10 feet high at maturity.
It’’s best to prune off flower buds at planting to allow the plant’s energy to go into root and stem formation rather than flower and fruit formation. Young plants require little pruning for the first two to three years compared to mature plants. Blueberries grow best when mulched. Mulching keeps the soil cool, conserves moisture, adds organic matter to the soil, improves soil structure, and aids in weed control.
After planting, apply a mulch of Douglas-fir sawdust or bark to a depth of 2 to 3 inches. Increase the mulch to a depth of 6 inches over a period of years. You may have to apply 25 percent more nitrogen fertilizer on mulched plantings compared to un-mulched plantings, depending on how fresh the sawdust is.
Fresh sawdust ties up nitrogen while it decomposes, so you need to add more for the plants. In late April of the planting year, apply 1 ounce of ammonium sulfate fertilizer (21-0-0). Add the same amount of fertilizer in early June and in late July. Sprinkle the fertilizer evenly within 12 to 18 inches of each plant, but not directly on the crown or stems.
Since blueberries have a shallow, fibrous root system, they’re susceptible to drought injury. A uniform and adequate supply of water is essential for optimum growth. Check the soil frequently for adequate moisture and irrigate if necessary. Each blueberry cultivar ripens berries over a two- to five-week period.
A well-managed, mature, high-bush blueberry plant will produce from 13 to 18 pounds of fruit. Don’’t be too anxious to pick the berries when they first turn blue — they are not yet fully ripe. They’’ll develop better flavor, become sweeter, and grow about 20 percent larger if you leave them on for a few days after they completely turn blue. The fruit should be picked about once a week or more often in hot weather.
The following cultivars are listed in order of ripening: Earliblue, Bluetta, Duke, Spartan, Patriot, Meader, Collins, Bluejay, Blueray, Toro, 1613-AIvanhoe, Olympia, Bluecrop, Berkeley, Rancocas, Pemberton, Herbert, Rubel, Colvile, Jersey, Dixi, Darrow, Lateblue, Elliott, Sunrise, Nelson, Sierra, and Bluegold.