I usually get up at 7.30. Gilles travels a lot with his work, so he’s either already left or he’ll be away on business for a couple of days. We have three children and I’m about to give birth to our fourth — which is like a gift because I’m 43. I love nothing more than being pregnant: it’s something beautiful, you feel like a tree that has lots of fruits on it.

We have our little routines to make things run smoothly. Etienne always wants to play with his toys, but Louise loves dressing up. She has a very poetic presence. I’ll get them ready, make their breakfast, and then have mine: muesli, an espresso with hot milk, and toasted bread with peach and mango jam. I buy organic bread from a wonderful bakery on rue de Fleurus called Bread & Roses.

While I get ready for work, our nanny arrives to take care of Iris and drop the other two off at school. My offices are on avenue Kléber, between the Trocadero and Charles de Gaulle-Etoile, and I can catch two buses. They both go by the Eiffel Tower and over the Seine, and while I’m sitting there I can’t resist guessing what fragrances people are wearing.

It’s like a barometer of scents in the city.

As you’d expect from a company that makes fragrances, there’s a huge number of scent molecules flying around our office. At perfumery school — I went to Givaudan’s school in Grasse — you memorise more than 3,000 smells, including flowers, spices, woods and herbs. As well as natural smells, there are also synthetic ones, and they often imitate natural ones. Most perfumes are a blend of both, because it’s impossible to distil the smell of certain flowers, like lilac or lily of the valley. Then others, like jasmine, never smell quite like they do in nature when they’re distilled, and need to be enhanced. And then there are flowers like the iris, which you don’t really think of as having a scent, but do. In fact, the iris is one of the most precious ingredients in perfumery — it’s like our caviar. The scent is in the iris bulb, which has to be dried for three to five years. Through a process of distillation, the molecules responsible for the smell come out in a thick, oily compound. Tonnes of bulbs are needed to make the smallest amounts, so it’s a long, expensive process, but it’s worth it.

At lunch I tend to go to the same place for weeks on end and order the same thing. At the moment it’s a bistro, where I have Argentinian steak with green beans. If it’s a Wednesday, I pop over to a market near the Alma Bridge. I love its bustle, the atmosphere, the smells.

When people ask me how I come up with a formula for a new perfume, I’m not sure I know myself. It’s like a wild bird that sings only when nobody’s watching. In a way, perfumery is like other creative processes, such as writing or painting, where you might have a theme or know what colours you’re going to use, but where there’s still that element of magic and it just comes out of you. Sure, creating a fragrance involves equations and formulas — that’s how it starts, with me sitting at a computer, imagining various combinations — but at its heart it’s an emotional process, evoking all sorts of things. A time, a place, even a person.

When I think of my childhood, I always think of my mother’s fragrances. They were part of her everyday life and she had different ones to suit different occasions, from Chloé to Rive Gauche. So did my grandmother. One of her favourites was Miss Dior. Then there was my aunt — she loved Chanel No 19. I used to sneak into my mother’s room and gaze at all her beautiful bottles. I’d smell them and then mix my favourite ones together. Sadly, my mother became very ill when I was 12 or 13. She had cancer. Towards the end of her life she lost her sight, but she’d still comment on smells, like foods, flowers, clean laundry, soaps, and of course her perfumes — beautiful things, things we could still share. After her death I went on to study philosophy at the Sorbonne but I really didn’t know what I wanted to do. Then one day I met a girl who told me she was going to perfumery school. I had no idea such a school existed — it was like an angel coming down to tell me. From that moment on, I knew what I wanted to do with my life.

I’m usually back home by 6.30-7. The nanny’s often given the children their dinner, but I’ll still get them to sit with me and Gilles, so they can tell us about their day. We eat a lot of fish. When the wild salmon’s in season, I always stock up. Gilles laughs because nothing else fits in the freezer. And I’m obsessed with artichokes. I love the moment you transfer them from the saucepan to the plate, because they look like flowers in full bloom. I like to pull the leaves off one at a time and dip them into a bowl of vinaigrette — that way you savour the leaf’s subtle flavours.

It takes me a long time to convince the children to go to bed, but once they have, I’ll run a bath. It’s easier in the evening — I can relax, take my time. I love using soaps, they’re less popular these days, but there are such beautiful ones around, like Valobra, Heno de Pravia and Yardley — I love their lavender ones. Before bed, I check on the children and pray that everything will be okay with the birth of the baby. Life is wonderful right now: I’m very much in love, I have three beautiful children and I have a job I’m passionate about. I am blessed and I count my blessings every day.

Interview by Ria Higgins. Photograph: Steeve Iuncker

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