I’m in the artist Peter Blake’s studio in west London. It’s in a two-storey industrial building on a quiet street next to a tube station and it’s crammed with the fruits of 60 years of collecting – cabinets of curiosities, toys, folk art, Elvis memorabilia, found objects, records and a life-size effigy of the African American boxer Sonny Liston that appeared on the cover of the Beatles’ Sgt Pepper LP, which Blake designed.

Blake, who has just turned 80 and is preparing for an exhibition of his work at the Waddington Custot Galleries in London, shows me a large canvas propped against a wall at the far end of the studio. It’s called Once Upon a Time and he’s been working on it, on and off, since 1964.

“I don’t think I’ll ever get it finished,” he says evenly in an accent from which the traces of Dartford and Gravesend, where he was born and grew up, have never been entirely expunged. “It’s one of those pictures that’ll be in the studio when I die.”

The fate of the studio and everything it contains has been on his mind a good deal recently. “I have an eye on when I die,” he says. “I’ve talked to Sandy Nairne [the director of the National Portrait Gallery] about a portrait show. That could end up being posthumous.”

In a sense, the studio, or rather the collection it contains, is Blake’s biggest and most ambitious work of all. Exploring it is like browsing through the contents of a particularly well-stocked mind. “It’s a very private collection,” he tells me. “It’s autobiographical.”

Junkyard jazz

I ask him where he thinks the impulse to collect or accumulate came from. “I was seven when the Second World War started. I was evacuated and was away for most of the war, so I kind of missed that bit of childhood between seven and 12. Then, after the war, I went to Gravesend School of Art. There was a junkyard nearby and I bought three objects: a papier-mâché train, an ‘outsider art’ painting of the Queen Mary, and a complete, leather-bound edition of Shakespeare. The passion to collect started then.”

I go upstairs, where the collection has been arranged fastidiously in a series of themed rooms. One of these contains some of Blake’s early drawings, including one of the Royal Festival Hall done in 1954, when he was at the Royal College of Art in London. He recalls the optimism of the postwar period fondly.

“Frank Auerbach was in the year above me. In the year after me were Richard Smith, Robyn Denny, Bill Green – the British abstract expressionists. It was an incredibly exciting time.”

He mentions Auerbach more than once. “I admire him enormously. He’s totally serious.” I’m being invited, genially enough, to draw a contrast with Blake. “When I turned 65,” he reassures me, “I retired from animosity, jealousy, ambition – all the unpleasant elements of the art world.”

“Peter Blake: Rock, Paper, Scissors” is at the Waddington Custot Galleries, London W1, from 21 November