The grape stompers were actual Italian women who didn't speak English. In a 1974 interview with Dick Cavett, Lucille Ball went in-depth on the making of the infamous scene in which she got in a fight in the grape vat, revealing that the fight was scripted but the other woman didn't understand that it was supposed to be phony, and as a result she wound up actually beating the hell out of Lucy. The audience and crew were oblivious to what was really happening and the fight stretched on so long that it had to be severely edited in the final cut of the show. Despite the hardships she endured during the making, Ball cited this as her favorite episode of the series.
When Lucy is approached by the Italian director on the train, Lucy begins to act dramatically, trying to impress the man. Lucy grabs her hair, messes it up (much like Italian actresses of the time) and recites the line: "The calla lilies are in bloom again." This is a quote from the classic Stage Door (1937), in which Lucille Ball had a prominent supporting role but always called her "big break". The film starred Katharine Hepburn and Ginger Rogers and included Ann Miller and Eve Arden in supporting roles. The line "The calla lilies ... " was Hepburn's character's first line in the play within the film, and is repeated numerous times throughout the story, most notably when Hepburn's character has opening night jitters and is convinced that she will forget it. In the documentary Hollywood the Golden Years: The RKO Story (1987), Lucy speaks glowingly about Katharine Hepburn, and it is probable that Lucy made a suggestion to the writers to include that line as an homage to her.
Actor Franco Corsaro spoke English as a second language. To learn his lines, Franco memorized all the lines including the other actors. This can bee seen on the train when the other actors yell "Has she ever considered acting?!" Coraso can be seen mouthing their lines in order to stay on track with his lines.
The grape stompers were supplied by a winery in California's Napa region. The winery's only request was to explicitly state in the script that wine making is mostly a mechanized process. Most grape stopping in Europe ended in the Middle Ages meaning by the 1950's wine making had already been mechanized in some form or another for hundreds of years.
This is one of two episodes specially colorized and combined, appearing as a one hour long 2013 Christmas Special on CBS, entitled the "I Love Lucy Christmas Special." The other being Season 6, Episode 11: The I Love Lucy Christmas Show.