How do you make a popular warm-weather destination even more desirable? By adding beer, of course. For the second year in a row, Boston’s Rose Kennedy Greenway hosts a beer garden near Rowes Wharf run by one of the city’s most acclaimed brewers, the Fort Point-based Trillium Brewing Company. The patio—also serving vintages from Westport River Winery—is expected to be open Wednesday through Sunday beginning in late May, and is scheduled to be joined down the road by another local favorite, East Boston’s Downeast Cider House, which is set to open its “Back Porch” in Dewey Square across from South Station at about the same time.