Wal-Mart has promised to buy more produce from local farmers as it kicked off its 'Locally Grown' program to highlight the fruits and vegetables grown in Oklahoma and sold in its stores, The New York Times reports.

The Arkansas-based company's 'Locally Grown' program looks to keep prices down for shoppers, support local economies, and slice shipping and fuel costs.

Wal-Mart plans to add signs in its stores to point out locally grown produce, and says its partnership with local farmers has grown 50 percent over the past two years.

Even without the added fanfare, shoppers can already purchase locally grown foods in neighborhood Wal-Marts. Some examples from Oklahoma include corn from Bixby, blackberries from Yale and mushrooms from Miami, said Angela Stoner, the company's senior public affairs manager.

The campaign was launched Wednesday at a Wal-Mart Supercenter on the city's south side, where Tulsa Mayor Kathy Taylor and state officials spoke in front of a display of peaches grown in nearby Porter. The orchard sells its peaches in more than two dozen Wal-Mart stores.

Taylor said buying locally helps the environment because of the reduced production costs, such as packaging. ''Buying green saves you green,'' said Taylor, clutching her own bag of peaches in a plastic Wal-Mart bag.

Buying local also adds to a consumer's peace of mind, especially after the recent salmonella outbreak in the U.S. that affected more than 1,000 people, officials said.

''It allows the consumer to have confidence in what they're buying,'' said Steve Thompson, the associate commissioner of the Oklahoma Department of Agriculture, Food and Forestry.

Nationally, Wal-Mart works with hundreds of growers to provide produce sold in its stores, and already buys more than 70 percent of its produce from U.S.-based suppliers, according to the company.

As one example, the company says it obtains more than 12 million pounds of peaches from 18 states. The local strategy saved more than $1.4 million in freight and gasoline costs.