Peonies’ showy spring and early summer blooms carry a sweet scent that many find appealing. But some plants produce flowers with a faint scent or no smell at all, and there are a handful of reasons for that.
Peonies are classified as their own species, but several varieties do not have flowers with any scent. These include Nippon Beauty, a Japanese variety. Some peony growers from the 19th and 20th centuries believed color was related to fragrance.
The weather can play a part in how much scent peonies emit. In warmer weather scent carries further and attracts bees.
University of Virginia studies suggest that even the scent of varieties known for their fragrance, and other flowers’ scents, are diminishing over the years, perhaps due to air pollutants.
University of Michigan floral scent biochemist Eran Pichersky theorized that peonies and other plants hybridized for larger, colorful flowers can produce less of a scent because pigment compounds are derived from the same chemicals as scent compounds. Plants damaged by frost or disease may also emit less of a scent.
When a peony flower’s scent cannot be detected, the problem may lie with the person sniffing it. Some people simply have a limited sense of smell.