Agnès Varda - Grande dame of the New Wave

Agnès Varda has been making films for more than 50 years and her Cleo from 5 to 7 was a landmark in French cinema. And she's not finished yet, she tells Sheila Johnston, who meets the director at her home

There is no sign or nameplate on the double-fronted house at the end of the Left Bank street. But you're unlikely to miss the facade, flamboyant and elegant, painted in shades of burgundy and dusty pink. This is the private queendom of Agnès Varda, vanguard New Wave film-maker (the lone female voice in that cosy all-boys club), national treasure, internationally fêted artist, grand octogenarian eccentric.

Inside, a warren of rooms are packed to the rafters with the treasure trove of a lifelong traveller and compulsive collector: Varda, 82, has lived here since 1951. A cabinet bulges with awards, both for Varda and her late husband, the director Jacques Demy. On a shelf in the hallway a Berlin Bear for Varda's Le Bonheur (1965) nuzzles up to an old teddy bear. Files are marked "Friends: France", "Friends: abroad", "Postcards".

Cats and people drift in and out. Mathieu, her son by Demy, breezes in. Rosalie, Varda's daughter from a previous relationship, lives next door. Isabelle Huppert is expected later. There's a welcoming, bohemian air to the place, and Varda herself, with her flowing, colourful clothes, round face and trademark pudding-basin hairdo, looks like a slightly bonkers little old lady, a role she cleverly exploits in the documentaries both to send herself up and to put her subjects at ease. But you quickly understand that she runs her show – as she must – with military precision.

"I haven't made that many films compared to some directors, but over 50 years, you build up a body of work," Varda says, and indeed she has been prolific. The features are only part of it: many of her movies are a mix of documentary and fiction, and she is a mistress of the pithy essay-film – 2008's The Beaches of Agnès, a light-hearted, compendious tour through her life and work, had a valedictory air. But it's soon clear that this was a false impression.

Arriving early, I find Varda across the road in a shop she has turned into an editing suite. Glued to the screen, she scrutinises footage shot recently in Mexico with a lightweight DV camera: skyscrapers, a peasant woman selling baskets at a market, the director Carlos Reygadas in his garden surrounded by agaves. She cuts the images together briskly, with a keen eye for detail: these fragmentary impressions will eventually coalesce into a six-part television series. "I love editing – it's at that stage that a film is created," she says. At one o'clock sharp, the pre-arranged time, she calls a break and we move to a little courtyard surrounded with plants for a "light lunch" (which, this being France, is naturally a simple but excellent five-course feast). Varda tucks in with the same voracious appetite she applies to exploring the world.

"I've always tried to do different things, not to repeat myself," she says. "But when I was looking for extracts from my films to use in The Beaches of Agnès, I did find a certain consistency. There are almost no night scenes – I don't like the night and I don't like shooting by night. And I've almost never filmed bourgeois characters in a bourgeois setting even though there are good stories to be told about them. I realised I was much more interested in giving a voice to people on the margins."

Varda's subjects have included fishermen (in her debut, La Pointe Courte, 1954), Californian hippies (Lions Love, 1969), Los Angeles mural artists (Mur Murs, 1980), a female tramp (Vagabond, 1985) and foragers, in The Gleaners and I (2000), an ahead-of-its-time documentary about the excesses of western consumerism. "People 60 years my junior came towards me after that because a lot of them are concerned about ecological issues. A young man paid me a lovely compliment: he said, 'Congratulations, your film is magnificent, it makes me want to be old'." Varda lets out a hearty laugh. "I said, 'Hold on, let's not exaggerate!'"

Summarised thus, her films sound earnest, but they are not: they're studded with throwaway humour. "They're all rooted in a difficult social reality, but I don't want to be Madame la Sociologue." Varda's one full-blown comedy, A Hundred and One Nights (1995), a fantasy with a stellar cast including Michel Piccoli, Jean-Paul Belmondo, Marcello Mastroianni, Catherine Deneuve and Alain Delon, was a critical and commercial flop. "People like to put you in a pigeonhole," she says, shrugging. "But I'm cool about it. If a film doesn't work, I'll move on to something else."

A new print of Varda's second feature, Cleo from 5 to 7, still looking bandbox fresh and trail-blazingly brilliant has recently been released. "People talk to me about it as though I'd made it yesterday," she says proudly. "Even though it was 50 years ago, my dear." The film – which contains set-pieces of great technical virtuosity – is in some ways a love letter to swinging Paris, tracking Cleo, a beautiful blonde, as she sashays through the streets. The action unfolds in real time. "The city authorities wouldn't let me change any of the clocks – they said it would confuse people – so if Cleo went past a clock in the story at 6.10, we had to shoot that scene at exactly 6.10. I had to prepare carefully and be very well organised. But it's exciting to set yourself constraints and challenges."

Worth the price of admission alone is a film-within-the-film, a spoof starring Jean-Luc Godard and his then-wife, Anna Karina. "We were close friends. When Luc lived with Anna Karina, we saw each other all the time; we went on holiday as a foursome. He was very clever but great fun too. He'd cut deals with cinema managers: 'If I walk through the lobby on my hands, can I get in free?' Perhaps his films are difficult for the public but he had an incredible reputation then because of the extraordinary success of Breathless."

Varda got funding for Cleo thanks to that, despite her own film's darker side: Cleo's charmed life is threatened by a premonition of mortality as she awaits the result of a medical test. "I thought, 'The thing that impresses me most about Paris is the fear. Parisians are afraid of everything. And the great collective neurosis of that era was cancer. My producer Georges de Beauregard – who had just made Breathless – said, 'OK, but you're allowed to use the word "cancer" once only in the film. And not near the beginning'."

Varda walks with a stick, but her energy is undiminished, like her contemporaries, in fact: Demy and Truffaut died in their fifties, but Chabrol, Rivette, Resnais and Godard are going strong. "They're all over 80 and still shooting. Me too. We're not dead and we're not stupid.

"But I think The Beaches of Agnès will be my last film on 35mm for the regular cinema circuit. Since then, I've turned towards the fine arts – I had a very big exhibition at the Fondation Cartier, for which I could do work that was more unusual. For instance I projected a little film of four or five minutes made purely of primary colours on to an inflatable beach mattress. You're much more at risk in an exhibition because people might or might not look, or just for a few minutes. But those who like what you do there seem to like it a lot. With old age, I've given myself that freedom. Even with this new television series, I'm having fun, creating associations of images and ideas that I wouldn't do quite the same in a normal documentary. I've always loved working and making things up."

At 2.30 sharp, Varda terminates our meeting.. "Talking to you, I've just noticed that this plant is turning towards the sun. I have to move it around now, because one side is suffering. And that will be the end of the interview." Not quite: first, she wants to show me some short films, including a television interview with Madonna, who hoped to star in an American remake of Cleo. By the time I've finished, everyone has vanished. I let myself out, armed with instructions from this tireless organiser on the best shows to see in Paris that afternoon.

'Cléo from 5 to 7' is on release around the country to 9 July (www.bfi.org.uk/releases); the Agnès Varda Retrospective runs at the BFI Southbank, London SE1 until 31 May