Fashion designer Nicole Farhi has turned her back on couture to devote her life to sculpture

Nicole Farhi, one of Britain's best known fashion designers, has ditched fashion for sculpture. She is holding her debut sculpture show next week in London, where she will exhibit 12 busts of famous names from the worlds of art, fashion, stage and screen.

These include many of her friends, including Judi Dench, Anna Wintour, Helena Bonham Carter, and Bill Nighly, as well as her playwright husband David Hare and her former tutor/mentor Eduardo Paolozzi. The prospect of her debut show titled, From The Neck Up, at Bowman Sculpture, which will also include a series of more abstract sculptures, is something she is extremely nervous about.

"This is a new experience and I feel entirely naked and alone to face the reaction of the public," says Farhi, 68. "I obviously had many fashion shows over the years but somehow, the anxiety of showing a new collection was shared by my team, and I spent more time calming those around me than concentrating on my own nervous state."

Farhi has been sculpting now for nearly 30 years. "I sculpted in the evening, at weekends and religiously took Wednesdays off to sculpt," she says, but more lately she has been sculpting full time for the last two years,

She works from a very old and large conservatory in the garden of her north London house which she shares with her husband, Hare, and her 98-year-old mother. "We tried to grow tomatoes and courgettes and grapes with absolutely no luck or success. It became my studio ages ago," she explains.

But she prefers not to have a sitter in front of her, instead working from photographs or memory, as in the case of Lucian Freud, Francis Bacon, Paolozzi, Tom Stoppard and Stephen Frears: "I have a rather good memory for faces, even if in life if have seen them only once or twice as in the case of Freud or Bacon," she says.

Usually her sitters will come to the studio to be photographed – then she will study them and adjust the clay models further when they come round for dinner – before she casts them into concrete, glass, aluminium or bronze.

"My husband, David, and my mother are the only ones who sat however briefly while I was working on their busts. And when I'm not sure I will spend time when in their company observing the person I am working on. I prefer to work on my own. I would feel inhibited I think if I had a sitter in front of me. When I make a bust I work on the back, the face, the profile, turning the bust endlessly on my stand. I cannot quite see myself asking someone to move every five minutes."

Farhi wakes up early at 6.30am or 7am and gets into the studio ready for a day's work at 8.30am or 9am, having done her mail. "My mother lives with us, so I stop at 12.30pm for a brief lunch with her," says Farhi. "I go back to the studio until 4pm, 5pm or 6pm. I am more creative in the morning. I will work in clay, do some modelling. In the afternoon, I am more technical, I do some casting. I don't speak much during the day, I like to work in silence."

The structure of the face "will appear or not", she says, after a few hours sculpting in clay. "Once I have the structure, the true character will follow – sometimes days later, weeks, sometimes months."

She finds beautiful women harder to get right because "it is as if their beauty acts as a kind of mask". "Judi Dench was the easiest woman to sculpt. I saw the young woman she was and still is through her smile. Helena Bonham Carter was the most difficult. I am still unsure of the result." American Vogue editor, Wintour, is an old friend who had attended all Farhi's fashion shows. "I did a few portraits of Anna. I asked her to sit for the photographs. It didn't take long, probably five or 10 minutes. It took me much longer to execute the work."

The French-born Farhi, who was raised in Nice, came to London in the early 1970s, after she had moved to Paris at 18 to study art. She worked as a freelance designer until she met her first husband , the entrepreneur, Stephen Marks, and started French Connection with him in the UK. She founded her titular label Nicole Farhi in 1982, with the backing of Marks, and was made an honorary CBE in 2007 for services to the fashion industry and was awarded the Légion d'honneur by her native France in 2010.

It was while a fashion designer that she met Eduardo Paolozzi at the Royal College of Art foundry in the late 1980s, while she was casting her first bronze during evening art classes. "We became friends and Eduardo took me to exhibitions and out to lunches," says Farhi. "He was teaching me not by telling me how to do things but by showing me how other people had or were doing things."

But a few years after meeting Paolozzi, Farhi married Hare in 1992. "Because I was so happy, I'm afraid I wasn't sculpting much. Eduardo kept saying marriage and happiness were not helping my work." So Paolozzi came to see her every Wednesday to get her to sculpt again. "He taught me to work in wax and plaster, which I didn't like very much. I very quickly went back to sculpting in clay. These were lovely days. Mornings in the studio, then lunch, then looking at books or going to an exhibition in the afternoon," she says.

"It is difficult to explain why Eduardo liked me but as he was interested in my sculptures, he was also interested in my work as a fashion designer and would find ways of putting into words my philosophy behind the clothes I was designing. He would prepare wonderful folders full of cuttings on different subjects to excite my curiosity. I learned something from him every time I saw him until he died in 2005."

Farhi's fashion career was nearly at its end when Marks sold the Nicole Farhi label in 2010 after the fashion group suffered big losses. As far as Farhi was concerned, "the passion and soul went with him", so she decided to leave her label behind in 2012. "I resolved to give the rest of my life to sculpting," she says. "When I had a fashion company, I was totally committed to be a fashion designer. I knew one day I will give all my time to sculpture."

From the Neck Up, Bowman Sculpture, London SW1 (bowmansculpture.com) 17 September to 3 October