BATAVIA, Ill. — Aldi opened its first eight supermarkets in Southern California on March 24, the first of 45 locations set to open in the region this year.

After growing slowly in the decades after its arrival in the United States in 1976, the German retailer’s U.S. division is accelerating the pace of its store openings. Aldi is in the midst of a five-year plan that calls for adding about 130 stores a year through 2018, when it will have about 2,000 locations, mostly on the East Coast and in the Midwest.

Aldi appeals to discount-minded shoppers, with spartan stores that offer few national brands. The company holds down labor costs by having customers bag their own groceries and by displaying many items on shipping pallets on the floor rather than paying workers to shelve them. A typical Aldi supermarket operates with about 20 ­employees.

The first eight Aldi stores in Southern California are located in the cities of Beaumont, Fontana, La Quinta, Lake Elsinore, Moreno Valley, Palm Springs, San Bernardino and Yucaipa. Another 19 stores are set to open from April to July.

Each store opening was celebrated with a ribbon-cutting. All shoppers who attended during a three-day grand opening event received a free Aldi reusable eco-bag, and the first 100 shoppers at each store received a ticket redeemable for gift certificates of various amounts. All shoppers were eligible to enter an on-site sweepstakes for a chance to win free produce for a year.