Interestingly, the camellia has been the state flower of Alabama since 1959. Prior to this change, the goldenrod was the state flower, but many of the ladies in Butler County, the county just south of the state capital of Montgomery, objected as goldenrod is a wild flower that was considered by many a mere weed.
Also of relevancy to the novel,a News article of January 3,2010 quotes Frank Kaplan as contending that 1959 was a monumental year for change because of advancements in biochemistry and technology:
But can a single year like 1959 really bear all that weight? Kaplan says the year was significant in civil rights - a federal commission held hearings, and the lynching of Mack Charles Parker triggered national outrage.
Mack Charles Parker was an African-American accused of raping a white woman in northern Pearl River County, Mississippi. Just three days before he was to stand trial, a mob kidnapped him from his jail cell in the county courthouse, and he was beaten and shot.
It would seem, therefore, that Harper Lee has Jem open the box in order to reveal the white camellia of Mrs.Dubose as a means of subtle foreshadowing of events to come. For, the white camellia is the harbinger of change as Scout loses much of her naivete in her observation of the trial of Tom Robinson, a man whose tragic life loosely parallels that of Mack Charles Parker.