What is the theme, or message, in the short story "Marigolds" by Eugenia Collier?

One of the central messages of this short story seems to be summed up in the main symbol of the story, the marigolds, and the narrator's actions in destroying them. From the start it is clear that the marigolds are a symbol in the short story, in that they have a meaning above and beyond their literal significance. The narrator is clearly puzzled by the marigolds, especially given the nature of Miss Lottie's home. we are told of the care that Miss Lottie takes in working on her marigolds, working on them "all summer". The children come to hate these marigolds. However, by the end of the short story, the narrator realises herself the symbolic significance of the marigolds, however, only after she has destroyed them