It can be argued that, in Shirley Jackson's short story "The Possibility of Evil," Miss Strageworth's roses symbolize the emotions Miss Strangeworth associates with a perfect, pleasant life.
By the middle of the story, we learn that Miss Strangeworth's roses are red, pink, and white. Characteristically, red roses symbolize passion; pink roses symbolize gratitude and appreciation; and white roses symbolize purity, even spirituality. All of these feelings are necessary for a pleasant, happy life. But, more interestingly, Jackson is drawing a connection between all of these feelings associated with roses and Miss Strangeworth's desires for perfection.
We see the connection between the roses and her desires for perfection when, early on in the story, Miss Strangeworth reflects to herself, "The roses belonged on Pleasant Street, and it bothered [her] to think of people wanting to carry them away." The name Pleasant Street represents her desires for all things pleasant and perfect; therefore, the fact that the roses belong to Pleasant Street shows us that she sees the feelings associated with her roses as only belonging to her, to the perfection she feels is Pleasant Street. Even more interestingly, her desire for perfection makes her the exact opposite of the feelings her roses represent; her desire makes her selfish, manipulative, ungrateful, unfaithful, and the exact opposite of religious.