Why do different flowers have different smells?

Candace Webb
23 January 2012

Above: Image © Public Domain

When most people think of flowers, they immediately think of sweet scents. But, this is not always the case. Not all flowers smell sweet. In fact, some downright stink. For example, the titan arum, a huge flower native to Sumatra, smells like a rotting carcass.

Flowers have unique smells because they attract different pollinators. For example, bees, moths and butterflies tend to be drawn to sweet smelling flowers, like roses, whereas insects like dung flies are attracted to flowers that smell like rotting meat. Bats prefer flowers with musty odours and some beetles like ones with strong, fruity fragrances.

Did You Know? The titan arum releases stinking steam at regular intervals to attract pollinators. Silent, but deadly.

Many pollinators and flowers have coevolved and are completely dependent on one another. Coevolution occurs when two or more species adapt to each other's changes. For example, some orchids' flowers have evolved to look and smell like the female of the wasp species that pollinates them. Male wasps try to mate with the flower, strike out, and move on. However, they carry the orchid's pollen when they leave.

Did You Know? When Charles Darwin found an orchid with a foot long tube of nectar in Madagascar, he predicted that a moth with a long tongue that could reach down and deposit pollen on the female parts, or ovaries, would be its pollinator. He was right! The giant hawk moth was found nearly 100 years later!

The chemicals responsible for floral scents are called essential oils, which are produced in the petals of flowers. Combinations of these oils are responsible for the distinctive smells of blooms.

Did You Know? Breeding of flowers to improve traits like colour and size, as well as the effects of pollution, has lead to a reduction in the scent of flowers, reducing the ability of flowers to attract pollinators.

Flowers are beautiful, but they're about more than looks! Next time you buy some pretty flowers for someone, remember you're not the only one trying to attract attention.

Learn More!

Candace Webb

I graduated from the University of Ottawa in 2006 with a PhD in Biology. I am now a postdoctoral fellow at UCLA, studying the funky circadian rhythms of plants. Besides science, I love to write, hike, paint, bike ride, and hang out at the beach.


Une diplômée de l’Université d’Ottawa, j’ai reçu mon doctorat en biologie en 2006. Je suis présentement boursière postdoctorale à l’Université de Californie à Los Angeles, où j’étudie les rythmes circadiens des plantes. En plus des sciences, j’aime écrire, passer du temps à la plage et faire de la peinture, de la randonnée et du vélo.



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Avatar  marguerite mccormack

know everything about flowers smelling.