In his lab, Aylmer tries to impress and amuse his wife by showing her a "perfect" flower that unfurls and blooms before her eyes. He tells her to pick it and smell its beautiful scent, also advising her it won't last long, but will leave behind a brown seed that will perpetuate its kind:

But Georgiana had no sooner touched the flower than the whole plant suffered a blight, its leaves turning coal-black as if by the agency of fire.

This perfect plant, created in the lab, symbolizes the perfection Aylmer also wants to create in Georgiana through science by removing her birthmark.

Aylmer says of what happened: "'There was too powerful a stimulus.'"

The flower most importantly symbolizes—and foreshadows—that Georgiana is too delicate for the powerful operation she is about to undergo. She will die like the plant.

Aylmer puts his love of science ahead of everything, including Georgiana's safety. His love of science represents his obsession with perfection. He cannot be satisfied with the world as it is, but must perpetually try to rid it of its blemishes. However, the outcome with the flower he has engineered shows the limits of his science. He cannot have the control over the outcomes of his experiments that he wishes, and a beautiful creation soon turns blighted.

The flower symbolizes the dangers of reaching too high with science. If Aylmer were not so obsessed with control and unrealistic goals of achieving perfection, he would have accepted his wife as she was and not killed what was a beautiful person with one superficial flaw.