What nature provides: botanical scents in perfumery

On a cold morning, a stone pine forest smells of almost nothing. On the afternoon of the same day, once the sun has shone on the trunks for a while, it smells of resin, so clearly that you notice it from a distance. The trees have not changed, only the temperature. And with it the amount of fragrant substances they release into the air.

Perfumery has always lived on such substances. But plants do not make them for us, and the path from tree to bottle is longer than you might think.

In short: Botanical fragrance materials are substances that plants produce for protection, for communication or to attract pollinators. They are obtained mainly by steam distillation, cold pressing or extraction, often with enormous effort. Modern perfumes combine such natural materials with fragrance materials developed in the laboratory, a partnership that began as early as 1889.

Why plants smell

For plants, scent is a language. Flowers use it to attract pollinators; wood and bark use their resins and other compounds to fend off fungi and insects. The heartwood of the Alpine stone pine, for example, contains pinosylvin, a substance that fungi and bacteria cannot tolerate, and which at the same time is why the wood keeps its scent for so long.

Sometimes this language is remarkably sophisticated. In 1990 the biologist Ted Turlings and his colleagues described in the journal Science what a maize plant does when caterpillars feed on its leaves: it releases scents that attract parasitic wasps, which then lay their eggs in the caterpillars. The plant, in a sense, calls for help.

And sometimes you can even see the scent of trees. On warm days many trees release isoprene and related compounds, which react with ozone in the air and form a fine haze. As early as 1960 the biologist Frits Went suggested that this haze helps explain the bluish veil over forested mountains. The Blue Ridge Mountains in the USA owe their name to this shimmer.

How a plant becomes a fragrance material

Most plant fragrance materials are obtained by steam distillation. Hot steam draws the volatile substances out of the plant material, condenses and then separates into water and essential oil. This is also how stone pine oil is made: in the Pitztal valley, where our oil comes from, a distillery obtains about one litre from roughly a tonne of chipped stone pine wood.

With flowers the ratio is even more extreme. A kilogram of rose oil from Bulgaria's Rose Valley takes 3,000 to 3,500 kilograms of petals. They are picked at the end of May and the beginning of June, and only between five and eleven in the morning, because the scent fades in the midday heat.

Citrus fruits, by contrast, need no heat at all. Their oil sits in tiny glands in the peel and is cold-pressed, which is why lemon oil smells so close to the fresh fruit. And for flowers that cannot withstand heat, solvent extraction is used. The result is called an absolute and is often the densest, most precious form of a scent.

Nature and the laboratory

For a long time every perfume consisted entirely of natural materials. That changed in the 19th century, in a way that suits the Alps rather well. The chemists Wilhelm Haarmann and Ferdinand Tiemann succeeded in producing vanillin, the main fragrance compound of vanilla. Their starting material was not the vanilla pod but the sap of conifers.

In 1889 Aimé Guerlain launched Jicky. It is considered the first perfume to combine natural materials with synthetically produced fragrance materials, among them coumarin, the scent of fresh hay, and a form of vanillin. And, as Smithsonian Magazine describes it, it was one of the first perfumes that set out to evoke feelings rather than simply imitate flowers.

Since then, nature and the laboratory have not been opposites in perfumery but partners. Some notes cannot be obtained from nature at all, such as an accord reminiscent of cashmere wool. Others could only be had at the expense of animals, like musk, which once came from the musk deer. And natural materials have a characteristic worth knowing: they are not the same every year. Weather, soil and harvest time change them, much as with wine. That is exactly what makes them alive, and it is one of the reasons a good natural material is so valuable.

What is in our fragrances

ARVE contains both. It begins with a natural material: stone pine oil from the heartwood, from the Pitztal valley in Tyrol, air-dried and steam-distilled. To this come essences and extracts from natural materials and further fragrance materials. Together with our perfumer Andreas Wilhelm in Zurich, we have combined them into two moments. A morning in ARVE Pétillant, with lemon, iris and vetiver. An evening in ARVE Chaleureux, with cinnamon bark, fig leaf and moss. We use no fragrance materials of animal origin.

What remains

Perhaps the most beautiful thing about natural materials is that they never quite stand still. A stone pine forest smells different in July than in October, a rose different in May than in June, and no batch of stone pine oil is exactly like the last. A perfume holds on to one of these moments. The forest takes care of the rest, every day anew.

Frequently asked questions

What are botanical fragrance materials? Fragrance materials obtained from plants, for example from flowers, leaves, wood, roots, resins or fruit peel. Plants produce them to attract pollinators, to defend themselves against pests or to communicate with one another.

How is essential oil obtained? Usually by steam distillation. Citrus oils are cold-pressed from the peel, delicate flowers are extracted with solvents.

How much raw material does an essential oil take? Often a great deal. A kilogram of rose oil takes 3,000 to 3,500 kilograms of petals, a litre of stone pine oil roughly a tonne of wood.

Are natural fragrance materials better than synthetic ones? Not in principle. Natural materials are complex and vary from harvest to harvest. Synthetic fragrance materials make possible notes that do not exist in nature in that form, and replace materials of animal origin. Most modern perfumes combine both.

What was the first modern perfume? Jicky by Aimé Guerlain, from 1889, is considered the first perfume to combine natural materials with synthetic fragrance materials.