Aldi is testing the online delivery game in three major markets.

The German grocer has entered into an agreement with Instacart to launch grocery home delivery service in Atlanta, Dallas and parts of Los Angels starting Aug. 31, according to Business Insider.

San Francisco-based Instacart will allow customers to order groceries from Aldi online and get them at home in as little as an hour. If successful in the three pilot cities, Aldi will roll out the program across the country, Aldi Vice President of Corporate Buying Scott Patton told BI.

“We would like to roll this out very quickly,” Patton said.

It is an effort by Aldi to start competing with other grocers already offering online grocery ordering and delivery. In Atlanta, Publix Super Markets, Whole Foods and Costco Wholesale are among some retailers that already use Instacart.

While e-commerce has created a tsunami of change in the larger brick-and-mortar retail world, it has taken longer for an impact on food sales to show, with some 9% of U.S. adults reporting that their households ordered groceries online at least once a month, according to a Gallup poll.

But the low numbers could promise huge potential for growth. Amazon's recent purchase of Whole Foods underscores that potential in industry experts' eyes.

Aldi, with 1,600 stores in the U.S., plans to pump $3.4B in order to up store counts to 2,500 by 2022, according to Fortune. Those numbers would put Aldi in third place among grocery stores, behind Walmart and Kroger.

While Aldi is a discount grocery chain, Patton told Fortune that the company does not think paying extra for Instacart services will deter shoppers.

“We are known for great quality and low prices,” he told the publication. “All different income levels want to save money.”