Blueberries are easy to grow -- even in containers

Growing blueberries is easy, with dozens of varieties available that do well in our Bay Area climate. January-February is the best time to plant them. Most gardeners grow blueberries in the ground, but there are varieties that are easy to grow in pots or containers on a sunny deck, along pathways or even lining your driveway. Some varieties -- Bountiful Blue, Burgundy, Misty, Northblue, Northcountry and Northsky -- also have leaves that offer excellent fall color.

If you plant both early- and late-season varieties, you can be harvesting fresh berries from May through October. If you have enough self-control to not eat all that you harvest, you can wash the berries, dry them off and freeze them for use throughout the rest of the year. Even after being frozen, these blueberries have much more flavor than most of the ones you will find at the supermarket -- and you can feel good about eating local produce as opposed to fruit that is flown in from across the world.

There are three primary types of blueberries: highbush (Vaccinium corymbosum), lowbush (Vaccinium angustifolium) and rabbiteye (Vaccinium ashei). Highbush varieties are split into two categories depending on their required chill hours. (Chill hours are the cumulative number of hours of temperatures lower than 45 degrees that are required by deciduous fruit and nut trees and vines for fruit production.) Northern highbush requires more than 1,000 hours and southern highbush requires from 150 to 600 hours.

Growing your own blueberries will be an exercise in patience -- the plants don't usually produce for the first two to three years; they begin full production by around year four or five. However, the payoff will be well worth it as most varieties will produce for about 20 years.

Planting in the ground

Blueberries like acidic soils, with a pH of 4.0 to 5.2. If your soil is heavy clay, you will need to amend with lots of organic matter like compost and/or peat moss. It's also smart to add soil sulfur (at a rate of 3 pounds to 7 pounds per 100 square feet) to the top 8 inches of soil when planting -- this will help lower the pH to the desired range. Many local nurseries will do a soil test for you to help you determine the type and makeup of your soil. You may need to add acidifiers on a regular basis, depending on your soil.

When planting, make sure the roots are spread out in the hole and completely covered with soil. Mix in 1/3 compost and some peat moss, which will keep the soil loose and well-draining. Then, mulch with wood chips and pine needles (especially cedar and/or pine) which will help maintain the soil's acidity. Water well after planting and continue to water thoroughly at least once a week.

Planting a variety of cultivars is highly recommended; some will not fruit without cross-pollination, but even self-pollinating cultivars will produce more heavily and produce larger fruit when planted among several varietals.

Recommended varieties include Earliblue, Misty, O'Neal, Sharpblue (early season), Jubilee, Legacy, Southmoon (midseason), Ozarkblue and Centurion (late season).

Planting in containers

Planting in containers allows you to more easily control the acidity of the soil. Potting soil that is formulated for rhododendrons and azaleas works well. Plants should be started in 5-gallons pots, then moved to 20-inch containers after a couple of years. After planting, apply 4 to 6 inches of mulch to conserve water and help moderate soil temperature. Fertilize with an acid-based fertilizer (10-10-10), splitting the recommended application into several small doses from February to September. Blueberries like moist, but not soggy, soil. Remember that containers dry out faster than native soil, so be sure to water thoroughly on a regular basis. Every three to four years you should remove the plant from its pot, trim the roots and replace the soil.

Recommended varieties: Earliblue, Northcountry (early season), Bountiful Blue, Burgundy, Sunshine Blue, Northblue, Northsky (midseason), Brunswick, Tophat and Bluecrop.

Bruce Gravens and several other Master Gardeners did a blueberry trial last year. The five taste-test winners were Jubilee, Southmoon, Sharpblue, Reveille and Bluecrop. In Gravens' experience, the amount of sun had much more to do with productivity than any other factor, so be sure to plant your berries in a spot where they will receive at least six hours of full sun.

Local nurseries should have many of the varieties listed here in stock.

Master Gardeners Bruce Gravens and Nancy Garrison contributed to this article. Have a question? Call the hot line, 408-282-3105, from 9:30 a.m. to 12:30 p.m. weekdays.