Control is the primary concern for tomato growers and shippers who use protected agriculture.

Shade houses, in particular, are gaining popularity in Baja California, Mexico.

Even growers like San Diego-based Andrew & Williamson, which grows in three Baja regions — with climates the company describes as ideal for tomatoes — to maintain consistent year-round supplies, acknowledges the utility of shade houses.

“Baja is the perfect climate for tomatoes, but we do use shade houses because of disease pressures,” said Mark Munger, vice president of marketing for Andrew & Williamson.

Protected environments cut a lot of worry out of the production process, he said.

“You grow something where it’s meant to grow, it requires a lot less inputs and lends itself to sustainable farming practices,” said Munger, whose company has grown tomatoes in Baja California for 25 years.

Growers and shippers cite numerous advantages protected environments provide, including higher yields, consistent supplies from season to season and fewer food safety worries.

“It takes out a lot of variables,” said Brian Bernauer, sales director with Oceanside, Calif.-based Fresh Pac International, which has eight shade houses in its grower network.

Most of those variables are out of the grower’s control in an open field, Bernauer said.

“You don’t have to worry about wind, rain, pests, and the watering and fertilization are different,” he said.

There’s also less time spent on culling, he said.

“The quality is outstanding for your premium quality,” he said.

According to the U.S. Department of Agriculture, acreage planted using protected agriculture increased nearly 40% from 2008-10, and growers say the trend likely will continue.

Several reported additional acres under some sort of protection this year.

“It’s a growing part of the business,” said Joe Bernardi, president of Nogales, Ariz.-based brokerage Bernardi & Associates, which also has an office in San Diego.

“You have the same acreage but more yield.”

Bob Schachtel, sales manager for San Diego-based Expo Fresh LLC, said one of his growers is converting to shade houses this year for the first time for that reason.

“It’s better fruit, a lot less No. 2s,” Schachtel said.

There is a downside to protected agriculture, Bernauer said.

“It’s costly to put up a shade house, but the industry is going that direction because that’s what the wholesalers and foodservice people want.”

In addition, if returns on field-grown fruit are low, they serve as a drag on shade house or greenhouse product, said Dick Spezzano, owner of Monrovia, Calif.-based Spezzano Consulting Service, which specializes in retail issues.

Retailers want top-quality fruit, too, and shade houses provide it, Spezzano said.

“If you have 70% No. 1s (in an open field), it goes up to 85% in shade houses,” he said.