In the story "The Chrysanthemums," I believe the flowers are symbolic of Elisa and her personal sense of value. The blooms are beautiful and strong, just as Elisa is. They are unusual from other flowers in the area, and it is safe to assume that Elisa is as well: she approaches life with vigor—she's not just a rancher's housewife.
Where her flowers are larger and more beautiful than the flowers of other neighbors, they grow exceptionally well in Elisa's garden. Elisa, too, is exceptional. She is very strong, driven and energetic. As the story progresses, we find she is not satisfied with not being taken seriously, but wants to be credited with being able: being just as good as a man.
When she finds the rooted chrysanthemums discarded by the roadside, it is as if someone has trampled on her perceptions of her value in the world. She had told the tinker who took them that if they were gently cared for, they would take root and thrive, and all he does is throw them away because he never cared about the flowers, only that she would pay him to fix household items.
Like the "spent" chrysanthemums she cuts down at the beginning because they are no longer valuable, she feels the same way as the truth of her place as a woman and wife in the world dictate who she is allowed to be, and what she is allowed to do.
The chrysanthemum is an ancient flower that dates back to the 15th century B.C. Named from the Greek prefix -chry which means "golden," which was its original color, chrysanthemums now are in a variety of colors with a golden center. Somewhat like a daisy with longer petals, chrysanthemums are symbolic of optimism and joy. For the Japanese, chrysanthemums, with their orderly unfolding are considered symbolic of perfection.
In John Steinbeck's story, Elisa channels her creative and reproductive powers into her chrysanthemums which she tends lovingly since her husband is always preoccupied with tending his ranch. Living with him in the Salinas Valley, a "closed pot" offers Elisa no outlets for her feminine nature. However, when the tinker arrives, Elisa, like the chrysanthemums "unfolds" and releases her feminine urges and optimism:
Her eyes shone. She tore off the battered hat and shook out her dark pretty hair.
"It's the budding that takes the most care," she said hesitantly. "I don't know how to tell you." She looked deep into his eyes, searchingly. Her mouth opened a little, and she seemed to be listening....
She was kneeling on the ground looking up at him. Her breast swelled passionately.
Believing that the tinker was genuinely interested in the flowers causes Elisa's nature to bloom. However, after she appears beautiful and perfect like her flowers in her womanhood and dresses to go to town, Elisa discovers the chrysanthemums and a broken pot on the side of the road, ending her romantic dream. They have become what the tinker called them, a "quick puff of colored smoke":
In a moment it was over. The thing was done. She did not look back.
Elisa's description of the flowers as having a "good bitter smell" suggests that like the chrysanthemum, the beauty of the moment is ephemeral, indeed.