As recently as 1997, California grew only 196 acres of blueberries but now it has about 4,500, which are estimated to yield more than 20 million pounds this season. That's still well short of Michigan, the nation's largest producer at 110 million pounds last year. But when California's plantings mature, its production may reach 50 million pounds, exceeding Oregon's, now the third-largest U.S. producer.
All of this has not come easily, however. It's taken the help of some long-lost heat-loving relatives from Florida, a slew of technical tricks and even a couple of exotic falcons to make it happen.
Indigenous peoples across North America have gathered blueberries and related species in the genus Vaccinium for millenniums. But the classic blueberries of commerce, a type called northern highbush, were domesticated just a century ago in New Jersey; they require cold winters, and moist, acidic soil rich in organic matter, as in their native forests. Such conditions occur rarely in California and, when they do, it's mostly in northern coastal districts.
Surprisingly, however, most other Vaccinium species are tropical, and the ancestors of blueberries probably arose in South America and migrated through the Caribbean islands to Florida and up the Eastern Seaboard. Florida has several wild species well adapted to warm winters, but with fruits that can be small, seedy or bitter.
Starting about 1950, breeders crossed these with northern highbush varieties to create a new low-chill type with large, tasty fruit, called southern highbush. The first such varieties, introduced in 1976, had commercial drawbacks, but beginning in the 1990s, Paul Lyrene, a University of Florida breeder, released a series of improved varieties that revolutionized blueberry cultivation in warm climates.
A visionary Oregonian, David Brazelton of Fall Creek Farm & Nursery, started promoting blueberries to skeptical San Joaquin Valley farmers in 1985; for many years, however, the results seemed unpromising, largely because growers had not yet mastered soil preparation techniques, which required adding tons of sulfuric acid solution and mulch per acre.
"You couldn't just stick blueberries in the ground and grow them," says Tom Avinelis, who farms 400 acres of the fruit in the southern San Joaquin Valley. "The plants would look a bit sick in the afternoon, and they'd be dead the next morning."
Around 1997, Brazelton discovered a fix for San Joaquin water-quality issues that were exacerbating the problem. "It released the plants from prison," he says.
The learning curve was still steep, as farmers gradually became proficient in site and variety selection, pruning and irrigation, but starting in the late 1990s, blueberry cultivation really began to take off.
Costs for growing and harvesting are high in California, compared with other areas, but so are the prices the berries get at market, due to fortuitous harvest timing. Coastal California blueberries start as early as February and peak in April and May; the San Joaquin crop begins in early May and peaks in late May and early June.
"It's all about timing and market window," Avinelis says.
Adding momentum to the boom, blueberries are a rich source of antioxidants, especially anthocyanins, and their perception as a healthful, convenient fruit has boosted demand around the world.
How do California blueberries compare with those from traditional northern growing areas? Surprisingly, there's not much difference in flavor between the northern and southern highbush types. Compared with the earliest northern varieties, the southern varieties are larger, firmer, milder and sweeter, with less of a wild tang, but that's also true of some modern northern varieties. California's constant sunshine may make our berries sweeter, but in general, the most crucial determinants of quality are proper ripeness and storage.
There are considerable differences, however, among southern highbush varieties, but varieties unfortunately are almost never identified at markets; the only way to choose is to grow your own or visit a U-pick farm. Two of the best varieties are Misty and Southmoon, each of which offers a good balance of sweetness and acidity, and a complex flavor.
Of the leading commercial varieties, grown for their productivity, Emerald tends to be tart and very large, while Jewel is sweeter and softer.
Coastal farms in Southern and Central California account for only 600 acres of blueberries, mostly in small plantings, but have a reputation for premium quality because the mild climate allows the fruit to mature over a longer period and thus develop richer flavor. The plants typically remain evergreen, instead of going dormant, as they do in most other areas; Randy Pudwill, a grower in Nipomo, produces fruit virtually year-round in hoop houses.
But no cakewalk
Most of California's blueberry acreage is in the San Joaquin Valley, where one grower, Delano-based Munger Farms, has 1,600 acres. Although in summer this is the warmest blueberry-growing area in the world, the plants, with their Florida heritage, do fine. Still, when it's 105 degrees during harvest in June, it can be difficult and expensive for farmers to pick the berries before they turn soft.
The Mungers have placed their largest bet, 1,000 of those acres, on new plantings farther north near Stockton, where the soil is naturally suited for blueberries, it's a bit less torrid during harvest, and there's enough winter chill to grow some northern highbush varieties.
"In the long run, the fruit quality in Stockton will be better," Kable Munger says.
Cold can be as much of a problem as heat. Breeders have introduced ultra-early-ripening varieties that bloom very early and are thus susceptible to spring frosts. All growers can do to prevent this is turn on sprinklers, which warm the air slightly, and pray.
Birds such as starlings and waxwings particularly relish blueberries and can devour thousands of dollars' worth in a few hours. To protect his crop, Munger hires a falconer who roams the fields in his pickup from sunup to sundown, scaring off the marauders with three trained aplomado falcons.
Ultimately, the greatest challenge to growers may be surging supply, both in California and worldwide. In mid-May, California blueberries were selling at wholesale for only about $3.50 a pound, near the cost of production. Labor accounts for about 70% of this cost and as retail prices come down, some growers say the only way they'll be able to survive is by machine harvesting -- usually done at night when the fruit is cooler and firmer.
Clearly, California blueberries have come a long way from the northern forests. And while industrialized production may have diluted some of the romance of their wild origins, it's still worth remembering, when you see local blueberries at the market, the heroic efforts that it took to get them there.