Liz Hurley: John Walsh meets Britain's most glamorous farmer

Outside blakes Hotel in London, a vast black limousine is being chamois-leathered by a chauffeur in a peaked cap. This is not a good sight. It means Elizabeth Hurley has arrived before me and is now sitting downstairs in the Chinese Room, haughtily irritated by my lateness.

She is famously grand, isn't she? Posh, steely and with no time for "commoners" (ie, non-celebrities), she's a byword in aloofness. She has the hauteur of a Himalayan lama. And she hates the press for banging on ceaselessly about her safety-pin dress, her boyfriends, her acting and the condition of her skin. All in all, this is going to be a nightmare.

But downstairs in the Chinese Room – a sort of elegant opium den with furnishings by Zandra Rhodes – there is no sign of her. Evidently I was wrong; it wasn't her limo after all. When she enters the hotel, five minutes later, you can hear her low, super-confident voice asking a stranger in the adjacent breakfast room, "Are you John?" (Surprisingly, he doesn't have the presence of mind to reply, "I'll be anyone you want me to be, darling".) When we meet, the sun appears to stream, inexplicably, into this subterranean boudoir. Her handshake is firm, her smile is friendly, if appraising, and her beauty, at 9.30 in the morning, is frankly astonishing. None of this is what I expected.

She orders a skinny cappuccino and plonks a tape recorder on the table between us, as if a mistake has been made and she is here to ask about my beauty regimen and range of swimwear. "I had a bad experience once, with a Condé Nast mag in America," she explains. "He misquoted me hideously, a mean and personal comment about someone I'm close to. But I had the whole thing on tape so it was nice to know I could play [in court] this incredibly boring interview if I had to." She notices my look of alarm. "Though I'm sure you're not like that."

Ms Hurley is full of compliments. At one point she tells me I have "a nice inner light" (which is perfectly true, but elicits coarse reactions when I mention it to friends). She is expert at batting the conversation back to her questioner. Like a duchess, she will Put You At Your Ease and then she will Draw You Out. She talks a blue streak, with (for a girl from Basingstoke) lots of showbiz gush. Her favourite word is "obsessed" which she uses about everything from diets to divas. Along with the dazzle, though, you can glimpse a real enthusiasm for life – even, dare one say it, a girlish jollity.

Her face is sparkling – no, hang on, those are real bits of sparkle, the stuff that little girls have adhering to their faces after a party. "Is there still some there?" she asks. "We were at a fundraiser last night, and were absolutely shattered by the time we came home. We made £1.75 million to buy electric wheelchairs. It was lovely. Elton played. Some very nice people donated auction prizes." Had she bid for them? "My being at these events," she says, choosing her words carefully, "helps them sell tickets. They like to be able to say they'll have... people in the public eye there, whom they can gawp at." Nobody has ever avoided a word as circumspectly as Liz Hurley here body-swerves the word "celebrities".

She came today by car. She drives everywhere, in London (she has a flat in Kensington) and in Gloucestershire, where she and her husband, Arun Nayar, have a 400-acre farm. Her days, she says, begin with the school run. Whaaat? I assumed she spent her mornings reclining on a chaise longue, leafing through style magazines. "God no, those were the good old days," she says. "For the past eight years my primary role has been mummy. We leave the house at 7.20am in the pitch black, driving on very scary, icy, narrow roads. And it's 24 miles to school. But it's still a nice way to start the morning, because Damian, my son, is very like me, extremely chirpy in the morning. So we chirp at each other."

Damian, whose father is Steve Bing, the property developer, film producer and billionaire cad, and whose godfathers include Elton John, Hugh Grant and Denis Leary, is eight, and clearly the apple of his mother's eye.

"I don't know much about only children. I was the middle one of three, and if ever I was alone with mum and dad, it was a rare moment. Damian's never had anything but that. The result is, he's phenomenal with a roomful of adults, he's completely at ease in a way I would never have been. I suppose if you've had eight years of full-on, controlling-lunatic mum, that's what happens."

Is he growing up fast? "Damian is currently obsessed with the word 'sex', spelt out as in S-E-X. He talks about it all the time. He knows the facts of life already. He's got the school play coming up next week, in which he plays Prince Charming's PR. He's very well cast." She beams. "And he's been writing a screenplay. I've done my utmost to keep him away from showbusiness. I don't talk about it. It's not really in his life. But he's obsessed. It's got to the point where I had to ring my LA agent, and say, 'Do you know anyone who knows Selena Gomez? I must get her autograph.' Do you know her? She's this huge teen star, in Wizards of Waverly Place. She's 17, and is also a pop singer, and she's his dream girl. I've had to beg for an autograph. We had posters arrive, signed 'I can't wait to meet you – Selena'. Damian just can't believe his luck. It's the one good thing about his mother's job, that he can get Selena Gomez's number."

His mother's job is so hard to pin down, though. Let's see. Being the face of Estée Lauder for 15 years. Being Hugh Grant's girlfriend. Being Hugh Grant's ex. Being a producer (with Hugh Grant) at Simian Films. Being an actress, in some pretty rubbish movies and two half-way decent comedies, in which she was genuinely funny as Austin Powers's classy (but unshagged) assistant, Vanessa Kensington. Being a TV presenter (on the short-lived Sky TV reality show, Project Catwalk). Being a tireless "face" for cancer charities. Being... you know, in the public eye all the time.

Having launched her own beachwear line in 2005 and designed swimsuits for the Mango brand in 2008, her new initiative is a range of low-calorie organic snack bars: fruit ones, oat ones and, remarkably, beef jerky ones. Every bar features a drawing of Ms Hurley reclining in a black minidress and pink gumboots. "I came up with them as in-between-meals snacks, probably more for girls than boys. They're a little pick-me-up because a lot of women like something sweet after lunch or dinner. I don't like walking away with a savoury taste in my mouth." One could argue that a lady who wants something sweet after lunch could always order a pudding – but the word "pudding" is presumably anathema to Ladies Who Want To Look Like Liz. More questionable is the presence of beef jerky in the Hurley range. While one can see a relevance of fruit bars to Elizabeth (since they're cute, sweet and rather juicy) it's hard to see the connection between an English rose and a snack that's barely a notch above Sowetan biltong.

"I've always been obsessed by beef jerky. When I did a movie with Ice Cube in South Africa [Dangerous Ground] I was much thinner than I am now, and all I ate was biltong. It was absolutely delicious. I hadn't heard of the Atkins [protein-only] diet then, but that's probably exactly what I was on. In California, everybody eats it all the time. If you go into a 7-11 in America, you're more likely to see beef jerky at the cash till than a Snickers bar."

It isn't, she explains, the kind of deal in which she lends her name to someone else's product. It's all her idea. "The snacks came about because of my farm. It's only a small organic farm, 400 acres, where we do beef, pork and lamb and a small amount of organic arable – oats and wheat, maybe a few crops. I wanted to do something which embraced how I feel about natural food and the organic way of living, but was also about keeping slim. We were brought up never to eat between meals, but I always did."

Is she a very hands-on farmer? "I've had to be. We calved very early this year because we had an escapee bull last year, so they were all bulled a little early..."

Whoa, whoa, I say. You'll have to explain these nouns used as verbs. We did what?

"Our bull escaped, and went on the rampage," she says evenly. "The calves were born in March, which was horrible because it was snowing and icy and frosty. We calve and lamb outside in the open, because we think it's healthier – but we don't have the facilities to do it inside even if we wanted to. My brother, who's my farm manager, was having the same problems on his farm. And his wife was ill so he had to leave us for a month. We were between farmhands at the time, so Arun and I had to do it all ourselves. We had to look after all the orphan lambs because we'd lost a few mums to liver fluke. At one stage I had three calves and 17 lambs in my laundry room, all of whom had to be hairdryed."

In God's name, Elizabeth, I cry. This is hardly the time to be thinking of hair-styling when you've a crisis of animal husbandry...

"We learnt from the vet," she continues, "if there's a calf or lamb in the field, and it lets you come near it, it's a bad sign, because they should scarper when a human comes close, and if it's cold to the touch, and its mouth is cold when you put a finger inside, it won't survive unless you pick it up and take it inside. You literally wrap them in a towel and dry them with a hairdryer, or they'll die of hypothermia. We now have tons of bottle-fed pets. And a TLC field for the ones we want to take particular care of. We take them out of the herd and put them in the field beside the house, where they're tickled and stroked. They're quite a handful, but very sweet."

Has she, I ask, read Hardy's novel, Far From the Madding Crowd? She seemed to be turning into Bathsheba Everdene and Gabriel Oak – the farm-owning milady and her sturdy farmer ally – at the same time...

She's become a keen environmentalist, although she sounds a mite knackered by "the whole organic thing". Being given instructions about animal husbandry, "and how our crops are grown, how we manage our woodland and do our ditches and do our hedges" may not be wholly congenial to this headstrong daughter of an Irish soldier and a British primary school teacher. Her early ambition was to be a dancer (she studied dance and drama at the London Studio Centre) and she always had an eye for glamour. "I went through a phase of loving Marilyn Monroe and copying her make-up. I loved Ava Gardner and Elizabeth Taylor – they were my idols, classically beautiful women. I had a picture of Liz Taylor on my mirror, and tried to copy her eyes in Cleopatra."

She's clearly aching to get back to Hollywood. "I've been offered many things in the past seven years. I'm always being offered comedies, American sitcoms, and I've a couple on the table that I'm almost tempted to do." The mummy role, however, won't go away. "I wanted to be at home for Damian until he's seven or eight. I've done short ad campaigns, flying to New York just for two days. And I look after two businesses, which I can do after he's in bed. He begs me to take him out of school. He says, 'Mummy, I'd do so well with a tutor. I'd love to be in your trailer.' But that's exactly what I don't want for him. I want him to go to the same school every day with his mates, not to keep moving."

Because her father was in the British Army, the Hurley family moved a lot in her youth. "But I've moved every two or three years of my adult life. I love moving. I love new houses. I'm always looking for somewhere else." She and her husband Arun are currently considering a des res in Rajasthan, India, where they were married. "It's a haveli, a town villa, in the middle of the tiger sanctuary. It's incredibly beautiful, and so peaceful you feel you could tap back into your creativity and do some real fashion designing."

And now Ms Hurley must fly, because she's due in Bicester Village to shoot a fashion special, "and advise people about bikini shapes. I'll have a gorgeous young model with me, who'll demonstrate the range, while I explain to people what kind of support they can expect." Gosh. Just how many bikini shapes are there? "Bikinis are bikinis," she says, dismissively. "Ties, rings, bits, embellishments. Different fabrics, trims and colours, different ways of enhancing a woman's bust or making her bottom look attractive." She raises a sardonic eyebrow. "But sadly, the bikini that makes you look slimmer has yet to be designed."

She hit 45 this week, on 10 June. Had it been a shock to think that both leaders of the coalition Government are younger than her? "An awful shock. When I started doing movies, every crew member was older than me. Now, if I do a fashion shoot, I'm the oldest person on set and I'm the one in a bikini. But I like the energy of youth. I was quite grown-up and trustworthy at 22. I think you're more tenacious at that age. And braver."

She isn't crazy about embracing plastic surgery any time soon. "It would be a pointless exercise to try and recreate one's youth. As one's career evolves, one just gets older. I can't imagine being brave enough to have anything to do with knives. If you've been quite lucky [by which she presumably means "been a dazzling beauty"] you'd be scared of making everything worse. For me it's about being 45 and looking as good as I can for 45. I love people who look great for their age. My mother was 70 this year. Sometimes she looks tired and sometimes she's bursting with energy and looks radiant and fabulous. I've bought her every cream in the world over the years, but she doesn't really use any of that stuff." She smiles. The sun bounces all over the Chinese boudoir. Infinitesimal sparkles light up her immaculately maquillaged face. "I'm not too much of a believer in external things to make the light glow."