Meaning: any of numerous plants widely cultivated for their showy single or double red or pink or white flowers
"And so do I!" the boy, who had once declared that he knew who had founded Troy, cried suddenly and unexpectedly, and he blushed up to his ears like a peony as he had done on that occasion.
Every snip of the scissors, as rose and peony and bluebell fell, seemed to chirp, "Mrs. Morgan is coming today." Anne wondered how Mr. Harrison COULD go on placidly mowing hay in the field across the lane, just as if nothing were going to happen.