Jilly Cooper: "I just think I'm a drip with no confidence"

It takes a heart of stone not to preen at all those, "Gosh, you are brilliants", even though you realise she says it to every boy, girl, dog, cat, and cockatoo for all I know. She has enough compassion to fuel a nunnery and enough sexual imagination to empty it in a hurry.

Her latest bonkbuster, Appassionata, does for the world of orchestras what her previous four have done for showjumping, polo, television and toyboys in her fictional county of Rutshire, and includes many of her familiar heroes such as dastardly Rupert Campbell-Black. It is a world of divinely masterful men, women who worry about their breast size, characters twee at times and robustly sexual [there’s a coupling on the glockenspiel] at others.

Her husband Leo, a publisher of military history who spends a few days each week at his London office, says her own life is entwined in her fiction (her sadly departed dog Barbara is forever immortalised as the mongrel "Gertrude"), and although he skims the books – he is only human – he coined the pun "sex and Chopin" for Appassionata.

Her mother adds that she was always attracted to preppy, blond, upper-class cads. Certainly, her own life is a sitcom, only more amusing and, sometimes sadly, over the top. It would be tempting, in this cynical age, to believe it is all a good marketing ploy, but the glorious thing about her is that she is genuine. No one could pretend to be that seriously dippy.

On the other hand, could anyone that seriously dippy spend three years writing such long books? Real life is a mystery, so we might as well relax at the wooden kitchen table in her Gloucestershire home for a delicious lunch cooked by her assistant, Pippa.

Buzzing from one topic to another, she says it’s too boring to talk about the book. "I just want to gossip, but I have to be so careful. In the old days you could come down here and we could get pissed and talk our heads off, but the hoo-hah changed the goalposts and one couldn’t say what one wanted."

The "hoo-hah" was the lurid publicity in 1990 when, after years of writing about her thrillingly satisfactory home life, it was revealed that Leo, whom she married in 1961, having first met him at 14, had been having an affair for years. All that seems over. Only the other day a TV producer was anxious to film them à deux. "He assumed we had hobbies, but I told him the only thing we do together is make love occasionally, and the BBC wouldn’t let him film that. He was frightfully embarrassed. More wine?"

She is 59 but could pass for a decade younger. "One worries about decay. I looked at myself this morning, when I was washing my hair for you, and the bright light hit me and I thought, ‘Pleated skin – not very attractive,' but if you’re busy you’re much more worried about finishing things. Are you all right, darling?" This remark is addressed to her dog, Hero, who I am trying surreptitiously to kick – he seems in a persistent sniffing state.

Glaring at me, from his perch near the breadboard on the table, is Simon Rattle, a furry black and white feline concoction with mean eyes, named after the conductor. "Isn’t he sweet?" says Jilly. "He likes you, so he’s going to do his number. He’s a bit mad, with a habit of jumping on your shoulders and clinging tight. It’s all right – except when you’re naked answering the telephone."

Not an activity I was contemplating, I mutter, but Jilly is all compassion again, this time clucking to the photographer about his assistant. "Will you feed your little girl? She looks so hungry. Would you like some potatoes to take away?"

It is time to ask questions. She interrupts. "When I wrote interviews I spent weeks trying to get them right. I’d love to teach journalists how to do it. Rule one – arrive looking absolutely sweet and friendly. It was so kind of you to bring me champagne. Rule two, cherchez les minicab drivers. They know about everyone.

"You should hear them on Mrs Mellor. They’d go to the stake for her because they think she’s beautiful, sweet and a bit wronged. I had one the other day who’d just driven Virginia Bottomley. She’s gorgeous, he said, even in a green track suit with no make-up after jogging. I’ve got a good new pun – the Arts Council [Mrs Bottomley’s responsibility] doesn’t have a Bottomley’s pit.

"Why don’t you write something lovely about her? The trouble is these days readers would think you’re a drooling thing. Someone ought to write a nice piece about Camilla Parker-Bowles too, who is absolutely divine. I love her dearly."

She is a neighbour, as is Ronnie Ferguson ("a wonderful man"), George Milford Haven ("a fantastically handsome polo player") and "Mickey Suffolk – the Earl of Suffolk and Berkshire – a lovely man. Everyone thinks he’s a bit like Rupert Campbell-Black, but Rupert isn’t any one person."

She enjoys living in the country, having moved from south London 15 years ago. "The awful thing about life is that nothing is ever quite perfect, is it? If you’re a writer, and you’re stupid, you have to go into this awful self imposed exile. I have Pippa and others who work for me, and Leo for four days a week.

"But I’m completely one track and can only write if I’m not surrounded by jolly, laughing friends pouring a drink down me. I have lots of mates here, but don’t see them, which is boring. Now I’ve decided I’m going to fool around a bit. It’s silly to say ‘no’ all the time."

Some sort of social round begins this week as she publicises Appassionata as well as a CD of music from the book – "the selection of someone who listened to Classic FM for a couple of years," sniffed one critic, but which Jilly describes as "faintmakingly beautiful. I listened to it in the bath and cried so much the water went cold with my tears."

The only disappointment is the postponement – for financial reasons – of a TV adaptation of The Man Who Made Husbands Jealous. "It’s maddening, a real tragedy for the actors who were expecting a break." Not that she was too keen on the Riders dramatisation, where the only resemblance to the book was the title. "It irritates me when they completely re-write it. All they really want is the name, but I know nothing about screenplays. It’s probably very difficult. I’ve seen a bit of The Man Who Made Husbands Jealous. There are some good dogs in it. Excellent casting of a Jack Russell."

Her research is phenomenal, judging by the seven pages of acknowledgments – oh, yes, "dear, gallant" Barbara is there too – for Appassionata. "I wanted to write something accurate. I think it’s quite jolly, but it was a sod to write – how do you make 86 characters in an orchestra? I kept losing them. Someone would have red hair in the first chapter and be totally different later. I never thought I’d finish it, but then my mind was concentrated enormously by the fact that my darling housekeeper announced last August that she was leaving [for marital reasons] on 1 October, so I finished in six weeks. It was sheer fear."

Fear, she adds, can be the parent of cruelty. "I think it applies to women bosses particularly. They are often unnecessarily cruel, and to their own sex, because they have to establish themselves. I’ve seen men bullies, but women are worse. The terrifying atmosphere you get in some womens’ magazines when they’re beastly to each other. I suppose it’s sacrilege to say women are shrill, but the decibel level of their voices when they’re together makes them that way."

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Through the French windows she watches Pippa hunting for Jeff the gardener – there are 14 acres. She giggles and says, "Leo’s worst thing - I love this - is having to wander around looking for the gardeners. That’s a terrible remark. How lucky to have a big enough garden to spend hours finding the gardeners."

She works in a cluttered gazebo at an ancient, second-hand typewriter, called Monica, bought in Cirencester in 1984 - "I’m superstitious. I think when Monica goes, I will" – and planned to learn the pieces performed in the book by concert pianist Marcus, son of Rupert.

As a child she played piano in duets with her father on the violin – "the only time I saw him cry. I’m trying to work out why everyone thinks music is so wonderful. Samuel Johnson said it was the only sensual pleasure without vice. Of course there’s snobbishness. One was brought up thinking Rachmaninov and Chopin were junk and Liszt was beyond the pale, but he is frightfully ‘in’ now.

"I’m not keen on modem composers. Some are good, but a lot are complete phonies. I don’t understand why they’d want to be phonies for so little money. At least I’m a phoney for a lot of money," she guffaws. "Have some cheese."

She must be wealthy now, but she denies it vehemently. True, she bailed out Leo’s business on a couple of occasions, is generous to her two children, now in their twenties, but four number one bestsellers provide a good income. She calls for Pippa. "I need the money, don’t I?"

"Yes, because she’s skint," agrees Pippa, a trifle hyperbolically. Jilly adds, still managing to smile, "I’m not being aggressive or paranoid, well not much, but it’s the one thing that makes me cross. Polly Toynbee wrote a vicious piece in The Times asking why I write such rubbish when I don’t need the money. That hurts. All I’ve done for the last three years is this book.

"Everyone says I must be worth about five million. I have a big family, children, a large house, masses of tax, animals, and I’m such a flake I’m not very good at hanging on to it. Don’t laugh. I promise this is true. People don’t see either the inside of your bedroom or your bank statement. No one has any idea whether you have ancient aunts or a cat with a cocaine habit..."

I glare triumphantly at Simon Rattle, who slinks quietly away. "I’m sorry to go on about money. It’s all relative. I’ll get myself together one day. I just think I’m a drip with no confidence. My insecurities must be so dreary for everyone else."

Don’t worry, I say, sensitively, although with a certain hardening of the lips. Insecurity is the well spring of talent. "All right," she whoops. "I’m very insecure. Would you like cream with your strawberries?" She hunts in the fridge, finds none, and calls for Pippa who points out it is in a jug on the table. "Oh, that sums me up. I don’t recognise it when it’s decanted. I’m a mess in the kitchen."

She is now planning a thriller in which she kills off another brute, Rannaldini, even though her agent advised, "Oh, darling, it’s out of genre," and then she hopes to write a novel about golf. "One gets the background right, and then turns them into the same larky characters. Appassionata isn’t a bad book, is it? I hope it cheers up a lot of people, and that’s no bad thing. I would love to write a serious, good novel. I probably couldn’t, but I think one ought to try. ‘Bottomley’s pit’ is such a good pun, isn’t it?"

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