Vivienne Westwood is talking tartan.“The kilt is a wonderful garment on its own, but tartans are absolutely brilliant,” she says. “It’s a heroic image, the kilt flying and the idea of climbing mountains in this garb with the wind blowing at you.”

And if you think that’s effusive, wait until she gets started on Harris tweed. It is simply “wonderful”, says Dame Vivienne. “You can’t make a bad anything with it. It lends itself to the body. The texture is brilliant; it’s tactile, yet it will take a form and hold it. And the colours are so atmospheric. It’s a misty, British thing. The clouds are lower as they come across the Atlantic, you don’t have the high clouds and blue sky of the Continent.”

Despite her long-standing enthusiasm for Scotland’s natural fabrics, Westwood is only now opening a store here — in Glasgow’s smart Princes Square mall. She will hope to fare better than designers such as Nicole Farhi, Katharine Hamnett and Versace, who have all opened, and closed, stores in the city. Glaswegians, who love ostentation, especially when it carries a designer label, will flock to the new Westwood outlet, which will offer everything from her Gold Label semi-couture line to cheaper ranges and perfume. But for how long?

It’s a bold move during a credit crunch. Westwood, a famous solipsist who lives on planet Vivienne and makes few concessions to the real world, does not see it quite like that. “I don’t really know too much about the ins and outs of luxury goods and economic markets,” she says, “but I do know that I make clothes that are supposed to last forever. I hope if someone is going to buy a Westwood item, it’s for life.

“Someone once asked me what anyone should buy this season and I replied: ‘People should buy nothing.’ What I meant was that they should stop to think about what they really want, removing themselves from the incessant bombardment of propaganda — the latest must-have in every magazine, the most-played advert on every channel.”

These are revolutionary sentiments in an industry where built-in obsolescence is obligatory and the old is swept out twice a year to make room for the new. But Westwood has never been part of the fashion mainstream and has enjoyed her greatest successes when rebelling against the orthodoxy of the day.

“My clothes are uncompromising, in the sense that they are what they are and are not trying to sell themselves to you,” she says. “They allow you to project your personality and are quite theatrical. They invite people to respond to them and to come and talk to you.”

But only the right sort of people, she adds mischievously: “You are not going to be bothered by conservative types coming up to you, because they won’t.”

Westwood’s route into fashion was as unconventional as the looks she went on to create. Born in 1941 in a Derbyshire village, she was working as a primary school teacher, married with a young son, when she met the flamboyant entrepreneur Malcolm McLaren in 1965. McLaren was full of big ideas. In Westwood he had found the person who could make them happen.

By 1970 they had a business and romantic relationship, as well as a son, Joseph. They opened their first shop, at 430 King’s Road in London, which started off selling teddy boy suits, moved through James Dean leather jackets and became Sex, stocking fetish wear and attracting a coterie of disaffected kids. McLaren’s masterstroke was combining the shop’s clothing with its customers, giving them guitars and creating the Sex Pistols. In the beginning their music was secondary; it was their distinctive, confrontational aesthetic that made the headlines. And that was all down to Westwood.

“My clothes allow someone to be truly individual,” she says, though that was easier in punk’s heyday of 1977 than today. “The majority of people on the street look quite dreadful. They are lazy in their dress and take no time to express themselves through clothes. Minimalism is a dominant force because people are so afraid of committing an error in taste.”

Excessive restraint has never blighted Westwood. Having designed the blueprint for punk, her first catwalk collection, Pirates, was based on the billowing, dandyish shapes of 18th-century menswear. Wildly coloured and boldly patterned, rakish and sexually ambiguous, it was championed by Spandau Ballet, Adam and the Ants and the then new style magazine, The Face.

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