Why Some Flowers Smell (And Why Some Don’t)

Our sense of smell is an often overlooked, but important feature in the human experience. Smells can strongly link us to our past, our memories, and the people and things we love. The sweet smell of lilacs in bloom; the heady delight of jasmine; or the familiar and comforting scent of an Alberta Wild Rose can immediately bring us back to a specific time and place in our lives.

All with one sniff.

However, it also can make you ask – why do some flowers smell, and others don’t?

The amount and combination of volatile compounds and essential oils in flowers will vary not only across types of blooms, but also among flowers of seemingly identical shape and colour. All of this is to help the flower do one thing – attract pollinators. But, just as with people, different pollinators are attracted to different scents (and some aren’t attracted to any scent at all) or are attracted at different times.

What attracts a bee, for instance, is a sweet daytime scent that increases with temperature (when bees are more active). Moths pollinate at night, so the flowers that rely on them for reproduction, like jasmine and honeysuckle, release their aromas in the evening. Flowers with a spicy, musty, or fruity scent are often most attractive to beetles for pollination. Fascinatingly, once flowers are have been pollinated, they tend to reduce their smell. This allows other unpollinated flowers a chance to attract a pollinator. Buds are less fragrant for similar reasons – they aren’t yet ready for pollination.

But what about all those flowers that don’t release any smell at all? First, it is important to note that the aromas that are noticeable to humans do not represent the full spectrum of scent in nature. Other creatures have completely different olfactory abilities to ours. Therefore, there is the possibility that some flowers don’t smell to us. Many flowers used in florist shops have also been bred to focus on colour and size instead of scent. Other flowers are pollinated by the wind or by water, and don’t require a scent to attract their pollinator.

Whether you love the smell of flowers or prefer a scent-free environment, at the very least, you now have some fun facts to share with other flower lovers!