Image source: Sprouts Farmers Market.

What: Shares of Sprouts Farmers Market, Inc. (SFM 2.76%) slipped last month, falling 12% according to data from S&P Global Market Intelligence because of a disappointing earnings report.

So what: Reporting first-quarter earnings on May 5, the stock fell 7% as the organic grocer reported weaker-than-expected sales. In an otherwise strong quarter, the company said revenue improved 16% to $993.2 million, short of analyst estimates at $1.01 billion. Comparable sales were solid, increasing 4.8%, and on the bottom line, earnings per share improved 20% to $0.30, better than the consensus by a penny. 

CEO Amin Maredia said "the results reflect strong engagement with the brand," adding that the company remains positioned for continuing growth. Considering the struggles of Whole Foods Market and other peers in the organic space, Sprouts' consistent same-store sales growth looks even more impressive.

Now what: Investors may have also been turned off by the company's lowered sales guidance since it now sees comparable sales growth of 4%-5% and overall revenue growth of 17%-19%, though the company said that was primarily due to a lower inflationary environment as prices on commodities like beef and dairy have come down.

Toward the end of the month, the launch of 365 by Whole Foods Market also emerged as a potential threat to Sprouts as the lower prices at 365 are more in line with Sprouts', but the stock price seemed unaffected by the opening of Whole Foods' new chain. Looking ahead, Sprouts has successfully weathered competition from Kroger and other chains that have invaded the organic space, and it looks poised to keep up its solid growth. Last month's drop offers a good entry point for new investors.