The harvest of the centifolia rose, a key ingredient to one of the world's most iconic perfumes, is in full swing in southern France. There wouldn't be Chanel Number 5 as we know it without the addition of this delicate pink rose, the open secret to an otherwise mysterious fragrance.

The smell of centifolia roses wafts through the air at the Mul Family Estate in Pegomas.

It's early morning and dozens of workers are busy harvesting blossomed rose flowers in this area near the town of Grasse, the world perfume capital.

Also known as May rose or Rosa centifolia in Latin, the flower is a rare gift: it springs here near the French Riviera for only three to four weeks a year during the month of May.

With a delicate and unique scent, the rose centifolia is a key ingredient for the legendary Chanel Number 5.

OLIVIER POLGE CHANEL'S HEAD PERFUMER "These flower fields are very important for us because they're the same that provided the ingredients for Chanel Number 5 when it was created. Number 5 was made with the jasmine and roses that grow here, and that possess a very special and distinct olfactory quality. This is why over the years we've made sure to keep this quality that contributes to Number 5's hallmark."

60 seasonal workers are employed at the Maison Mul fields during the rose harvest. The job is entirely conducted by hand and involves picking the flowers by holding and rotating them before detaching them from the stem.

Immediately after the harvest, the rose petals are put into burlap sacks and swiftly brought to the nearby Sotraflor factory for the extraction of their scented essence.  

FABRICE BIANCHI FAMILY DIRECTOR, MUL FAMILY ESTATE "The secret is somehow to waste as little time as possible between the harvest in the fields and the loading in the extraction plant, so as to extract and have a quality product."

At the factory, the roses' aromatic essence is captured through a multi-step process called solvent extraction.

400 kilograms of roses are necessary to produce 1 kilo of this brown, semi-solid material.

In a small bottle of Number 5's most concentrated perfume, there's the essence of no more than 12 centifolia roses. But a little goes a long way in keeping up with perfume tradition and preserving a fragrance legend.