BURBANK, Wash. – Ten years ago, Jim Lott had never even tasted a blueberry, let alone thought about planting the fruit at his southeast Washington farm.

Then came reports about the fruit’s health benefits, an onslaught of consumer demand and blueberry-laden products, and research showing that soil additives such as sawdust could help give the bushes the acidic soil they crave.

Today, Lott has 125 acres of juicy blueberries to harvest.

He isn’t alone. Blueberry acreage has exploded worldwide – from British Columbia to South America and the United States to China – leaving some to wonder how much growth the market can bear.

Maine is the nation’s leader in the production of wild, or low-bush, blueberries, which are smaller than cultivated berries and deeper in color. About 60,000 acres of blueberries are grown on the state’s fields and barrens, yielding an annual crop valued at more than $75 million.

Prices for fresh blueberries have begun to level off after several record years, and processors are waiting longer before committing to buy from growers. Fruit marketers, too, are trying new tactics, including promoting blueberries in China and Canada – not to increase U.S. exports, but to keep those countries’ blueberries inside their own borders.

But more growth is on the horizon, raising worries of a market crash.

“The whole industry has been doing really quite well, but it has grown so fast over the last couple of years that returns are starting to drop pretty sharply,” Lott said. “All of a sudden, there’ll just be too many blueberries one year, and they won’t be worth anything.”

Worldwide blueberry acreage has more than doubled in the past decade from 62,800 acres in 1997 to 144,800 acres last year, according to the U.S. Highbush Blueberry Council. Most of that growth was in the Western Hemisphere – some 50,200 additional acres in South America and 32,000 more acres in North America, primarily the United States and British Columbia.

The harvest is expected to keep growing since commercial blueberry bushes need four to five years to come into full production. Add in the fact that most blueberry farmers grow only the one crop, and it’s easy to understand their concerns about oversupply.

“We’ve had the best of both worlds: increasing supply and increasing pricing, really driven by the whole health interest in blueberries,” said Mark Villata, the blueberry council’s executive director. “We have to continue to keep supply and demand in balance for the blueberry growers.”

In the late 1990s, researchers began touting the health benefits of blueberries, which are high in vitamins and antioxidants. By 2003, consumers had taken note: Demand for processed and frozen blueberries suddenly shifted to the fresh market.

Unlike other crops, blueberry growers can decide on a daily basis whether to sell to the fresh or processed markets. More growers in recent years have turned to the fresh market to try to meet demand, causing prices for blueberry processing to explode.

Processors paid growers about 85 cents per pound in 2002. By 2006, it was $2.15.

Now those same processors are biding their time, waiting to see if the market balances out, said Rod Cook, president of Naturite Foods, a marketing agent for growers primarily in the frozen market.

“A lot of people who traditionally buy from growers, they’re not committing, and it’s creating a lot of uncertainty in the market,” he said.

Steve Erickson, president of Pan American Berry Growers in Salem, Ore., said he’s witnessed several ups and downs in the blueberry market.

“This industry was due for a tremendous growing pain, and I think this year is the first year of the effects of that. It’s due to the success of the crop – farmers do jump on each others’ bandwagons when there’s a successful crop,” he said. “How long it will last will depend on whether the average consumer can continue to afford our crop.”