Shot on location in and around Nogales, Arizona, because the real Oklahoma in 1955 was so heavily farmed and developed that few suitable areas could be found that resembled the highly-rural and undeveloped Oklahoma of the turn of the century when the musical is set.
Finding "corn as high as an elephant's eye" proved to be quite a challenge. Since filming was to take place out of season, no tall cornfields were to be found anywhere. The job was given to the people of the University of Arizona Agricultural Department, who planted each stalk in individual containers and held their breath. With rain and good luck, the corn grew to a height of 16 feet, causing Oscar Hammerstein to quip: "The corn is now as high as the eye of an elephant on top of another elephant."