Rhymes of passion: Betjeman's women

"The sort of girl I like to see," wrote John Betjeman in The Olympic Girl, "Smiles down from her great height at me./ She stands in strong, athletic pose/ And wrinkles her retroussé nose./ Is it distaste that makes her frown, So furious and freckled, down/ On an unhealthy worm like me?/ Or am I what she likes to see?"

The note of furtive, self-abasing English lust is entirely characteristic of his early poetry – though not necessarily of Betjeman himself. He, from first to last, adored women and contrived to sleep with lots of them. He ran a wife and mistress simultaneously for 33 years. But, in his poetry, things are rather less rosy.

In a world of weekend tennis parties in Surrey and Berkshire, of agreeable country houses with labradors, butlers and sensible matrons dead-heading roses with trug and secateur, Betjeman's poetic alter-ego exists in a chronic fever of sexual excitement. Everywhere he looks there are girls to be adored, clear-skinned, fresh-faced athletic goddesses in pristine shorts and crisp cotton blouses, untying their Hermès scarves to let their hair blow free when taken for a spin by a chuckling lothario in an MG.

The Betjeman lecher often sounds like a voyeur or a stalker, peeping and lurking and plotting to seize his chance. He is a shocking fetishist. In The Olympic Girl he wishes he were "her racket press'd/ With hard excitement to her breast." In a late poem, "Senex", he is overcome with inconvenient desire as he ponders an array of girls' bicycle saddles. In Pot Pourri from a Surrey Garden he eulogises: "Pam, you great big mountainous sports girl," and faints with longing for her sturdily masculine allure: "See the strength of her arm, as firm and hairy as Hendren's;/ See the size of her thighs, the pout of her lips as, cross,/ And full of pent-up strength, she swipes at the rhododendrons,/ Lucky the rhododendrons."

Lucky indeed. At various times, in different volumes, she reappears as Myfanwy, a strapping, super-confident "chum to the weak", or Bonzo Trouncer, another Aphrodite in shorts, or Laurelie Williams, Queen of the Hunt Ball. But the last word in Betjeman Girl was Joan Hunter Dunn, who has died aged 92.

The poem he wrote for her, A Subaltern's Love Song, a paean of rapture over a posh tennis partner, is full of the now-familiar Bertie Wooster-ish hopelessness of the nervous lover, but full too of the quivering social dread of the outsider. He tries to mock the upper-class world that is second nature to Joan, even as he itemises its cars, and gardens, its verandah and summer house, in a dazed rapture. He worries about changing for dinner, and the "ominous, ominous dancing ahead". He is out of his depth socially, and drowning in love.

Of his love for the girl "furnish'd and burnish'd by Aldershot sun," there can't, however, be much doubt. He employs a favourite erotic image, of the "warm-handled racket" parked snugly back in its press, and considers the blazer and shorts casually thrown on her bedroom floor. She is his perfect girl. And the ambiguities of the poem inspired by the real-life Ms Dunn show how much she got under Betjeman's skin.

Betjeman's biographer, Bevis Hillier, is convinced that, though the poet had a huge "crush" on Ms Dunn, he never made a pass at her and they stayed platonic friends.

They met in London during the Second World War, at the Ministry of Information where they both worked. He was in the films division, she in the catering department. In December 1940, Betjeman was 34, married, and with his first child, Paul. But he engineered a meeting with the girl with red hair, in the office of a friend called Michael Bonavia.

As Joan came through the door, Betjeman sank to one knee, and she burst out laughing. He asked Bonavia if he might take her to lunch, was given permission (she herself seems not to have been consulted) and, in the taxi to the restaurant, showed her a copy of Horizon magazine and said, "I hope you don't mind but I've written a poem about you." She was, she said, "Overwhelmed - actually, all that about the subaltern and the engagement is sheer fantasy, but my life was very like the poem."

Her life was the object of Betjeman's love, quite as much as her burnish'd skin. He came from a comfortable middle-class background; his father was a successful furniture-maker of Dutch ancestry. Bullied at school for having a German-sounding name when the First World War was raging, he fell in gratefully with the smart jeunesse dorée at Oxford in the 1920s (Evelyn Waugh, Cyril Connolly, Anthony Powell et al) and, through them, found his way into the country-house-weekend set. There, floundering a little among the nobs, he compensated by romancing the ladies. He fell in love and proposed to many girls who bore surnames to make any social climber tremble, including Camilla Russell and Pam Mitford.

In a 2001 BBC documentary, John Betjeman: the Last Laugh, one of his conquests, Wilhelmine Creswell, now Lady Harrod, painted an unflattering picture of Betjeman the party animal: "He was just a sort of joke we all knew, really. His hair was like last year's nest. And his teeth were covered in green slime." It didn't, however, stop him from proposing to Ms Creswell, nor she from accepting. But it got nowhere. "It was just a thing John did," the fiancée recalled later. He liked girls and he liked the idea of being in love. So we got engaged, but it didn't mean anything."

Things were more serious with Penelope Chetwode, the daughter of Field Marshal Lord Chetwode. They were married in 1933, moved to a farmhouse in Uffington on the Berkshire downs, where their son Paul was born in 1937 (a daughter, Candida, followed in Ireland in 1942). Within a year of tying the knot, Betjeman was having sex with the housemaid, and continued to have "crushes" and liaisons with many women throughout his long, happy but peculiar marriage.

They were a violent pair. "John and I used to have physical rows," Penelope recalled in the BBC documentary. "We used to kick each other round the house. I remember once, it was frightfully funny, we were sort of pushing each other round the house, and Cyril and Jean Connolly were in the bath together. They hadn't locked the door, and we went in, kicked each other round the bathroom, with Cyril and Jean sitting in the bath, astounded. Then we kicked each other out again."

The rows with Penelope weren't always so frightfully funny. Sometimes they left him shaken and weeping – but generally he could find another lady friend, like his old pal Margie Geddes, to hug him until he stopped trembling.

By all accounts he loved his wife but could not bear their quarrels. She became preoccupied with her own interests – horses, India, mountain-climbing, Catholicism – and gave him enough space to fall for other women. The great coup de foudre in his life was his meeting with Lady Elizabeth Cavendish in 1951. The daughter of the 10th Duke of Devonshire was, at 25, a lady-in-waiting to Princess Margaret. Betjeman was 45, a journalist, reviewer and poet.

They met at a dinner in Mayfair given by Lady Pamela Berry, the political hostess. Dinner was delayed when one of the guests failed to show up: it was Guy Burgess, and he failed to attend because he'd just defected to Moscow.

Betjeman and Elizabeth did not speak to each other all evening, but a connection had been made. They became friends, then lovers and, for 30 years, her mother's house in Edensor, on the Chatsworth estate, became their trysting-place and the poet's second home. He kept a flat in London, seldom inviting his wife up from the country to stay. Betjeman, who used to call his wife "Filth". enjoyed a lot of sex. "When John was with Elizabeth," wrote Hillier, with masterly tact, "she ministered to his comfort in a way that Penelope rarely did."

Penelope knew about Elizabeth, but did not force the issue. Elizabeth told him she didn't want to break up the marriage, and tried to keep her distance, but failed. Betjeman told friends he felt torn apart because he loved both women, and could give up neither. If he gave up Elizabeth, he said, he knew he'd never again write anything of consequence.

The poet's long affair with the duke's daughter remained an open secret among friends until 1973 when – now knighted and made Poet Laureate – Betjeman moved (with Lady Penelope) to a house in Chelsea five doors away from Elizabeth. The press came a-calling and the ménage a trois was suddenly all over the media.

The end of Betjeman's life was a rather inelegant battle between wife and mistress to decide who should be his principal carer. When he was bedridden, they worked alternate shifts at the Chelsea home. He contracted Parkinson's disease and suffered a stroke in 1981 while visiting Elizabeth.

In April 1984, he spent Easter with her at Chatsworth and died a month later in Cornwall, with her by his side. He was buried there, and his long-suffering wife had to rush down from London for the funeral. It was considered all jolly awkward for those attending.

Shortly before he died,, Betjeman was asked if he had any regrets about his life. "Yes I have," he said. "Not enough sex." From the tennis-playing Amazons of his twenties to the elderly, scrapping handmaidens of his dotage, women – their mystery, their strength, their powerful arms and soft flesh, their confidence and their ministrations of comfort – took up the lion's share of his life's attention. It he didn't have enough sex, it certainly wasn't for lack of trying.