With 408 stores in operation, Whole Foods plans to cross the 500-store mark by 2017, and Walter Robb, co-chief executive officer, expressed confidence in the chain tripling its store base over the long term. This news comes on the heels of a strong first quarter, with sales up to $4.7 billion, more than a 10 percent increase. Additionally, Robb discussed programs that will affect produce pricing and labelling.

The company has seen unit lift from lower produce pricing in several test markets. "It is too early for conclusive results, particularly given the holidays," he said in a conference call, "however, we are looking at expanding the test to additional markets, as we believe more competitive produce pricing will greatly benefit our overall value perception.

"We see more opportunity for the Whole Foods Market brand than ever before," Robb noted. "The demand for fresh healthy foods continues to surge, and we are best positioned to benefit as the leading retailer of natural and organic foods and 'America’s Healthiest Grocery Store.'"

The company has also launched a Responsibly Grown rating system, which assesses growing practices that affect human health and the environment and prohibits some of the most harmful pesticides. "We believe these ratings draw clear lines of differentiation between our produce and floral departments and those of our competitors," he said. "The program has been well received by suppliers and customers, and close to 60 percent of our produce is already rated. We have seen the power of our differentiated standards in other areas such as meat and seafood and believe our Responsibly Grown ratings will see similar success over time."

Whole Foods has also seen a great deal of progress with its goal to achieve full GMO transparency. Just two years after setting a deadline for full transparency by 2018, it has more than 25,000 certified organic items and over 8,500 Non-GMO Project Verified products in stores.

There was also good news for the company's grocery delivery program. "We are now providing fresh grocery delivery options to more homes in America than any other food retailer," Robb said. "Since announcing our 15-market partnership with Instacart in September, our average weekly online delivery sales have already passed the $1 million mark. With online delivery sales as high as 5 percent of total sales in some stores, we are very excited about the future potential as we expand our reach to more markets, provide richer content highlighting our quality standards, and broaden our product offering."

The chain has also refreshed 40 stores and is on track to complete 200 by year end. "While results vary depending on the scope of the project and a variety of other factors, stores typically see an immediate sales lift, and we expect these investments to be one of the many factors contributing to sales momentum this year and beyond," he said.