Baby blues: Laura Marling on hits, heartache and that tricky 21st birthday

Laura Marling was so young when she started that the bouncers wouldn't let her in to her own gigs. Now 21, with a Brit in her pocket and a sell-out tour ahead, how is our 'most gifted young singer-songwriter' coming to terms with fame?

Laura Marling is running late, so I get a call from her publicist asking me to wait outside her house in a leafy street near London's Shepherd's Bush. Nice place, I think, as I park myself on the front steps; those albums must be flying off the shelves. Ten minutes later an apologetic Marling arrives lugging bags of groceries, lets us both in and tells me that it isn't actually her house. Her friend owns the top flat and recently let out her spare room to Marling for the rare periods that she's not on tour (before that, she was sleeping on a friend's sofa). Marling looks a little forlorn as she explains that none of the stuff here belongs to her. Her things have been in storage for more than a year and, despite 300,000 combined album sales, a Brit Award, two Mercury Prize nominations and a performance on Glastonbury's main stage under her belt, the new poster girl for folk music is still too skint to get a place of her own.

Upstairs, Marling makes us both tea and we sit at the kitchen counter. Lighting up the first of many cigarettes, she explains that she doesn't mean to sound ungrateful for her success. "No one starts playing my kind of music to make a fortune. But I do want to keep doing what I do and I do want to continue selling records. And I would, eventually, quite like some money."

Twenty-one years old, Marling is less waifish than she appears in photographs – though, with her grey-blue eyes and ghostly complexion, she still has the intense, windswept look of a Brontë heroine. She is wearing a faded grey sweatshirt, skinny jeans and battered plimsolls, and her white-blonde hair is all over the place.

The singer isn't big on dressing up – as demonstrated at the Brit Awards earlier this year where she was anointed Best British Female Artist, seeing off the nation's sweetheart Cheryl Cole in the process. Amid the billowing gowns and daffy hats, she clambered on to the stage in trousers, a plain top and her hair pulled into an untidy bun. Her acceptance speech amounting to little more than a mumbled "This is really weird," she was clearly baffled at her win – as were much of the mainstream media. The following week, Heat magazine asked: "Who IS Laura Marling?"

Marling has yet to match the global success of her friends and one-time backing band Mumford & Sons, though her star has risen at a remarkable rate, buoyed by the endless – and justified – stream of superlatives deployed by music critics, some of whom have put her songwriting on a par with that of Bob Dylan and Joni Mitchell. The Independent's Andy Gill called her "the most extravagantly gifted young singer-songwriter operating in Britain today".

She isn't intimidated by such accolades, partly because several years ago a musician friend advised her never to read what was written about her, be it good or bad, but also because "the kind of success I have had means I can still walk around London and get on the Tube and do what everyone else does. It means there's less to live up to."

Marling went to this year's Brits largely out of curiosity and because, "If I hadn't gone, my mum would have killed me." It was, she says, "the strangest evening. I assumed that if you were going to win you would already have been told. I took two friends and we were sat miles from the stage. We were on a table with lots of people in suits feeling ridiculously out of place. It felt like an out-of-town office party. And then they bloody well called out my name."

The phone didn't stop ringing for two days. For the first time in her life, she was even approached by a stranger who had seen her on telly the night before and wanted to know what kind of music she made. "But that was it," she recalls. "It all died down after that and life went back to normal."

Marling is a serious soul for whom music has nothing to do with awards ceremonies and media opportunities and everything to do with her rich and complex interior life. Her songs, which have dealt with love and parenthood, mental illness and death, aren't explicitly autobiographical, though she says they are generally rooted in some sort of experience. Writing them can be arduous and requires total isolation and immersion. "I would never sit and write a song in front of anyone, because you're so vulnerable. I don't know at what point in the process that it becomes acceptable to pass them on. When a song wants to be written, it will be written. When it does come, I will very rarely go back and edit lyrics. I'm quite a rational human being, and the only part of my life that I can't rationalise, or can't make sense of, is how a song gets written or why."

There was a feeling, when she released her first, start-lingly accomplished album Alas, I Cannot Swim on her 18th birthday, that Marling wasn't quite cut out for the job she had chosen. Her singing had a steeliness that belied her delicate appearance, but on stage she looked petrified, either staring intently at the floor or keeping her eyes clamped shut. Despite being hailed as part of a new generation of folk artists including Noah & the Whale and Mumford & Sons, she seemed uniquely detached from the industry in which she operated. But lately, with the release of her third album A Creature I Don't Know, a more self-assured Marling has emerged: one who can meet the adoring eyes of her audience and write songs with a playful streak.

"Now when I go on stage every night I know that it's my choice to be there," she reflects. "I get a weird kick out of it. It's like a pain in your tooth that you can't help pressing. It helps that I have been very lucky in that I've had people understand the way I wanted to do things. I've been able to put up certain barriers and have certain rules and restrictions that have been very important to me. I'm incredibly neurotic and a control freak. I like the thought that if there's going to be anyone to blame it's going to be me."

So, while Marling's not posing for the paparazzi just yet, she has "loosened the reins a bit. Although like anyone I can be blinded by temptation. If you'd asked me three years ago to go to the Brits I'd have said, 'Oh fuck off!'"

Born in 1990, Marling was brought up in Eversley, a semi-rural village in Hampshire. "At the end of my parents' road is a sign saying 'Welcome to Jane Austen country'. It's very pretty and sweet." She started playing guitar at the age of six, encouraged by her father, who worked at a recording studio, and later by her music teacher, who saw in Marling the beginnings of a serious talent.

She got a scholarship to Leighton Park, a private Quaker School in Reading, and there developed an irrational fear of death which is still manifest in the terror she feels when getting on a plane. Throughout her teens Marling was, she says, "extremely withdrawn. I was not a functioning part of teenage life. I was quite a recluse. My stupidity was in my believing that I knew all there was to know. I genuinely thought I had the world pegged. I was an incredible misanthrope. I couldn't relate to people my age, and I'm not sure why, as I wasn't particularly smart or interesting."

Contemporary pop music was never really on Marling's radar – her parents are ex-hippies still in thrall to the troubadours of the 1960s and 1970s, among them Joan Baez, Joni Mitchell and Neil Young. She and her sisters had occasionally been known to watch Top of the Pops but only when their father wasn't around. "I was basically given a lesson in music quality. The only band that my parents liked that I didn't was Queen."

She thought for a while that she might become a writer, but her love of music won out. She began putting her songs on MySpace and swiftly earnt the attention of Virgin Records. She left school at 16 after completing her GCSEs and having tried and failed to do A-levels. "I couldn't maintain the academic work and the music. By this time I had been signed, and had been on tour. I think I'll forever have a hang-up about not finishing my education, which is probably why I read so much now. I was really lazy."

Her upbringing was "very liberal". Her parents treated their children as equals and, as they got older, allowed them to make their own decisions. Thus, when their youngest announced, at 16, that she was moving to London, they didn't bat an eyelid. "It sounds a bit irresponsible, doesn't it?" Marling smiles. "To be fair, I already had a record deal, both my older sisters were in London and could keep an eye on me. And I've never been particularly wild."

She toured with acts such as Jamie T, Johnny Flynn and as a singer in Noah & the Whale, and had a year-long relationship with the latter band's singer Charlie Fink, who went on to write an album about their break-up. She formed her own band, too, comprising members of Mumford & Sons (last year she also dated singer Marcus Mumford). In that first year Marling "spent all my time either sitting in the back of a Ford Fiesta with a drum on my lap, or in my flat writing songs". Hilariously, she was once refused entry to one of her own gigs for being underage, prompting her to busk outside on the street instead.

Nowadays, she has no problem being identified by over-zealous doormen – and her raised profile has resulted in a ferociously busy schedule. Next week she will fly to America to play a series of live shows that her record company hopes will help her replicate the success of the Grammy-winning Mumfords. When that is over, she will return home and, in a novel twist on the homecoming tour, perform a series of concerts in cathedrals across Britain.

But while Marling insists she will never tire of making and performing music, there are areas of her life she'd like to adjust. At the grand age of 21, she is already tiring of city life. "Last night I got home from a festival at around 3am and the downstairs neighbours were having a blazing row. I was just lying there in bed thinking, 'Why did I come back? I could be in the countryside in the peace and quiet.'"

Time for a change of scene? "At some point, yes," she replies, thoughtfully. In the middle of last year Marling returned home from a particularly punishing tour and went to work at a friend's farm. It was "the absolute antidote to the illogical life that I lead". Her jobs involved being "elbow deep in sheep, shovelling shit, all that stuff." On her very first night she went out with the owner to shoot rabbits. "At the end of my stay I took two back to London with me on the bus. I skinned, gutted and filleted them, made them into a pie and ate them. Living off the land like that, albeit for a short time, felt right. The luxury of being able to pass one's later years like that would be phenomenal."

Marling the rabbit slayer – one imagines this isn't quite the image fans have of this quietly sensitive songwriter, but then she has often spoken of the disparity between the person she projects in her songs, which invariably find her at her lowest, and the person she really is. Along with her dreams of running a farm, she would like to write short stories, though is frightened that "it's just pen and paper, with nothing else to hide behind. That will be another mountain to climb at some point."

While Marling is not the type to divulge the secrets of her love life, past or present (the most she will confirm, to her visible discomfort, is that she's currently single), she is heart-warmingly open about her desire to have children. A while ago she was talking to her friend Ruth, who plays cello in her band, about the prospect of parenthood.

"She told me that though she loved what she was doing she was basically just passing time until she could have children. It was the first time I'd heard someone of my generation say explicitly, 'I'm a woman, and I want to be a mother.' And in some ways, I'm just passing time until I can have children. I love music and I will make music always, but this lifestyle is already getting to me."

Marling giggles absently as she outlines her fantasy idyll of tilling the land, making endless rabbit pies and popping out children, all in between making albums in the home studio at the bottom of her enormous garden. She draws on her cigarette, looks out of the window and exhales. "Everyone's got to have a dream, right?"

'A Creature I Don't Know' is out now on Virgin. Laura Marling's When the Bell Tolls, a tour of British cathedrals, begins at Exeter Cathedral on 14 October. For more information, visit lauramarling.com