Flowers' Last Dance: Fragrance And Death

Flowers are often associated with beauty and fragrance, but do dying flowers give off more scent? Flowers rely on their fragrance to attract insects, which are necessary for pollination and the production of seeds. The fragrance of a flower is produced by oils that eventually evaporate, spreading their scent into the air. As flowers age, they produce fewer scents, making them less attractive to pollinators. However, some flowers have evolved to mimic the smell of decaying flesh to attract insects that feed on carrion. These flowers give off a stronger odour to lure in specific bugs, such as flesh flies and dung beetles, which are then trapped and forced to pollinate the flowers. While most people associate flowers with pleasant aromas, some flowers emit putrid odours that can be compared to faeces or rotting animal carcasses. Interestingly, these scents can be used to create homemade fragrances and cleaners, or even to make potpourri, candles, and bath products.

Flowers attract insects with their fragrance

However, not all insects are fans of floral scents. Some insects, like mosquitoes, are attracted to sweet and fruity scents, but not necessarily flower fragrances. Alcohol can also make you more attractive to mosquitoes, as drinking raises your body temperature and increases the amount of ethanol in your sweat.

On the other hand, insects like bees are drawn to herbal scents such as oregano, basil, lavender, and peppermint. These plants have powerful scents that frequently entice bees.

Interestingly, some flowers have evolved to mimic the smell of rotting carcasses or feces to attract flies, dung beetles, and other insects that feed on decay. The "dead horse lily," for example, lures blowflies with the scent of a dead horse and traps them inside the flower to ensure pollination.

Pollination is aided by insects

Beetles, bees, flies, wasps, butterflies, and moths are all insects that aid in pollination. Bees are well-known pollinators, with bumblebees using their bodies to vibrate and dislodge pollen from flowers, which they then comb into baskets on their legs to take back to their nests. Honeybees are also important pollinators, and plants that are pollinated by them exhibit special adaptations, such as bright colours and pheromone production.

Other insects also have unique relationships with certain plants. For example, fig plants need to be pollinated by fig wasps, and in turn, the wasps live inside the figs and feed on them exclusively. Butterflies tend to prefer red flowers, while moths are attracted to white flowers.

In addition to these insects, even species with a bad reputation, such as houseflies and mosquitoes, play a role in pollination. Spiders, which are closely related to insects, can also be beneficial to plants by driving away florivores that might destroy the flowers.

The importance of insect pollination extends beyond the individual plant. An estimated 84% of EU crops and the vast majority of wildflowers depend on insect pollination. Insect pollination is crucial for the production of fruits and seeds, which are used for plant propagation, human consumption, livestock feed, and various industrial applications.

Flowers produce their own unique fragrances

Flowers have been used in perfumes for thousands of years, with the first recorded perfumer being a woman named Tapputi, mentioned on a tablet from Mesopotamia, dating back to 2000-1001 BC. Today, flowers are still commonly used in perfumes, with perfumers seeking originality, subtlety, and novelty in their fragrances.

The scent of a flower can vary depending on the species, with some flowers producing sweet and spicy fragrances, while others emit putrid odours of feces and rotting carcasses to attract insects that feed on such substances.

The process of fragrance production at the molecular level is complex. It involves the combination of multiple molecules, some of which can be perceived by humans, even though they originally evolved to attract pollinating insects.

Research into how flowers produce their unique fragrances is ongoing. Scientists like Sylvie Baudino have been studying the biological processes involved in rose scent production and the diversity of fragrances emitted by different rose varieties. They have discovered that roses follow a unique biosynthetic pathway involving an enzyme called NUDX1, which has potential applications in perfume production.

Flowers spread their fragrance through the evaporation of oils

There are several methods used to extract fragrance oils from flowers, each aiming to capture and preserve the delicate aromatic compounds. One common method is steam distillation, where steam is passed through the flower material, causing the volatile aroma compounds to evaporate. The steam and essential oil vapour are then condensed and collected separately. This method is suitable for flowers like lavender, tagetes, and geranium.

Another method is solvent extraction, which uses a solvent such as hexane or ethanol to dissolve the aromatic compounds from the flower. The solvent is then separated, leaving behind a concentrated fragrance oil. Solvent extraction is often used for delicate flowers such as roses, jasmine, and tuberose.

A traditional and labour-intensive method is enfleurage, which involves placing flower petals on a layer of odourless fat, such as lard or vegetable oil. Over time, the fat absorbs the aroma compounds, and the fragrance compounds are then separated from the fat using alcohol.

More modern techniques include supercritical fluid extraction, which uses carbon dioxide as a solvent, and maceration, which involves soaking flower materials in a carrier oil for an extended period.

The process of extracting and utilising the fragrance oils from flowers is a complex blend of art and science, requiring an understanding of chemistry, volatility, and evaporation rates. These oils not only provide enchanting scents but can also offer therapeutic properties, making them valuable in various applications, including perfumes, candles, and personal care products.

Flowers with a sweet smell

Flowers have a unique and charming smell that attracts us, and for a good reason. Smell, out of our five senses, is scientifically proven to be the most powerful and the one most directly connected to our memories. Familiar scents can instantly bring back memories, along with the exact emotions attached to them.

Gardenia

Gardenia, one of the most fragrant flowers, produces one of the most beloved scents in the garden world. Its scent is described as intoxicating, velvety, and warm, with honey-orange tones that match the aesthetic of its creamy, porcelain-white petals. Native varieties of gardenias, carrying scents often compared to jasmine, are also popular across India and South Asia, where the flower is traditionally called "Gandharaj," meaning "king of fragrances."

Rose

Roses, classic and iconic, have bloomed in the wild for nearly 35 million years and have been used for various purposes, from medicine to food to bath herbs. Their aroma is diverse, ranging from rosy, musky, citrusy, myrrh, to fruity scents. With over 150 species and thousands of hybrids, you're sure to find a rose that delights your senses.

Lily

The tiny, bell-shaped blooms of the lily emit an unmistakable, sweet, and virtuous fragrance. Stargazer lilies, in particular, have a heady scent that can fill an entire room with a sweet, spring-like perfume. However, it's important to note that lilies' pollen can stain surfaces and is toxic to cats, so be sure to remove the pollen-laden stamens before bringing them indoors.

Magnolia

Native to the Himalayan mountain ranges of Southeast Asia, the magnolia possesses a distinctive deep-grape and sweet, banana-like fragrance that suggests the first sip of champagne. Its scent is a favourite among global aromatherapy experts and Chinese natural wellness practitioners, evoking feelings of tranquility and calmness.

Jasmine

Jasmine, found across the world in over 200 varieties, boasts a rich and charming scent actively extracted by florists and perfumers. The standard white-flowered jasmine offers a breezy and enticing floral sweetness, but there are also varieties with sweet, musky, fruity, spicy, or vanilla-like fragrances, each intoxicating in its own way.

Freesia

Freesia is a bell-shaped flower that blooms in lined succession along a single stem. It offers a fresh and radiant strawberry-like scent with a zest and tingle reminiscent of the first sip of strong tea. With a wide range of hues, including white, golden yellow, red, orange, pink, mauve, and multicolored varieties, freesia delights both the eyes and the nose.

Honeysuckle

Honeysuckle, a plant often smelled before being seen, has a nectarous, vanilla-honey blend with hints of jasmine and lemon. The English honeysuckle (Lonicera caprifolium) and Japanese honeysuckle (Lonicera japonica) are among the most fragrant wild varieties. Sucking the honeyed nectar from the base of the blossom is a timeless summer pastime for people of all ages.

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