In most versions, including the original stage play, the Riffs are battling the evil Sheik. In the 1943 version, starring Dennis Morgan, released during WW2, they are battling the Nazis.
Practically all of the lyrics for "The Riff Song" have been rewritten, even the words that did not have to be changed. This was common practice in several Broadway musical adaptations made before 1955; it was done frequently in the Nelson Eddy- Jeanette MacDonald operettas and it was done in the 1954 film version of "The Student Prince". Movie studios did this so that royalties from all sales of sheet music for the film versions would go to the studios that made the films, not to the original lyricists. Exceptions included the 1936 film version of "Show Boat" and all of the songs except "Cotton Blossom" in the 1951 "Show Boat", as well as the 1943 film version of "Girl Crazy".
When Margot Birabeau (Kathryn Grayson) is singing "One Flower in Your Garden" she reaches over to a rose bush and removes a long-stemmed rose with no effort instead of having to cut it free. She then handles the stem without being pricked by the thorns, revealing that the rose is artificial.