Bentonville, Ark.-Walmart customers will have to look someplace else in the stores for their fertilizer and other such needs because more than 1,700 of the retailer giant’s garden centers across the country are being transformed into Game Time Headquarters, stocked with items to appeal to tailgaters. Walmart officials indicated the marketing change was being made to make better use of the space during a time when gardening sales slack off and interest in the local football teams reaches a peak. They point to tailgating.com, which reports 42 percent of tailgaters spend more than $500 each season on food and supplies. So, beginning immediately, these areas will become Game Time Headquarters, where shelves will be stocked with team merchandise and décor, as well as game-time snacks and beverages. Some observers, however, caution that Walmart risks confusing shoppers and alienating garden center shoppers, even though these items will still be available during the promotion, which runs through Sept. 30.