Kroger Co.’s recently launched Boost loyalty program that provides delivery discounts has already taken flight, thanks largely to greater Cincinnati customers.

Cincinnati-based Kroger (NYSE: KR), the nation’s largest operator of traditional supermarkets including Pick ‘n Save and Metro Market stores in Milwaukee, rolled out Boost in November in four markets: Cincinnati; Atlanta; Columbus, Ohio; and Indianapolis.

“In just a few short months, Boost membership is growing rapidly,” Kroger chief merchant and marketing officer Stuart Aitken said at the company’s annual Business Update event last month in Groveland, Florida, for analysts and investors.

Aitken said Kroger’s Ocado automated warehouse and distribution facility that opened a year ago in Monroe, just northwest of Cincinnati, provides the best example of Boost’s growth. Of the Kroger customers who use that Monroe facility, 30% have signed up for Boost, he said.

A similar Ocado warehouse is expected to be completed this spring in Pleasant Prairie.

Read more at the Milwaukee Business Journal.