Lisa Hannigan - Dawn of fame for down to earth diva

From idyllic rural upbringing, all nature and play, to a Mercury prize nomination, Ben Walsh charts the enigmatically sweet Lisa Hannigan's trajectory

I've seen Back to the Future and if you change one thing then everything else changes," explains Lisa Hannigan. The 28-year-old Irish songbird betrays no bitterness whatsoever about one of the most defining moments of her career. The singer bagged her big break when she bumped into Damien Rice in the student bar at Trinity College, Dublin, and timidly told him she could sing.

She swiftly became his backing singer, eventually lending her breathy, ethereal voice to the Irishman's wildly successful debut album O and his follow-up, 9. For many, her sumptuous harmonies were the best thing about Rice's songs. But then she was hit by a Rice bombshell or, indeed, cannonball. In 2006, just before taking to the stage in Munich, Rice blithely informed her she was no longer in the band. Being abruptly ditched before a gig is surely pretty harsh. However, the studiously calm Hannigan just doesn't seem to see it that way.

"Harsh? No, it was fine. I really don't mind at all," she maintains. "Sometimes things like that are a push. It's actually an easier sort of push than a more feeble way of doing it." But just before a concert? It must have been devastating.

"It happened the way it happened," she shrugs. "I can't remember how he phrased it; it was a couple of years ago now." But it was as harsh as Matt Damon ditching Minnie Driver on The Oprah Winfrey Show, wasn't it? "It wasn't as horrible as that," she laughs.

She is excruciatingly phlegmatic about it. In fact, a contradictory reticence punctuated by moments of perkiness characterises her conversation, which takes place in a tiny, serene space at the back of Union Chapel in north London, where she takes some time admiring a "particularly fat pigeon" nibbling on bird seed. Later that evening, inside the chapel, she plays an exuberant and sensational 17-song set, which includes a Bob Dylan cover, "Just Like Tom Thumb's Blues", and a brief slice of Michael Jackson's "The Way You Make Me Feel".

"The first concert I ever went to was Michael Jackson at Lansdowne Road," she says. "I went in a bowler hat, which I tried to push down and make Michael Jackson-like, but the hat just wasn't made that way."

The wide-eyed singer from County Meath is on the cusp of stardom: her album Sea Sew went platinum in Ireland; she has appeared on the comedian Stephen Colbert's provocative chat show in the US, performed on Dermot O'Leary's Radio 2 show recently, where the diminutive host effused over her voice and her performance of her single "I Don't Know", and, to cap it all, she is one of the 12 Mercury prize nominees. Hannigan, like Barack Obama in 2008, certainly has momentum.

"I really can't believe the Mercury nomination," she admits. "For myself, the lads in the band, Una, Nurse, Ben, and all of the people who worked so hard to put this record out and be heard – it's an incredible honour and unbelievable gift."

It sounds like a Sally Field acceptance speech, but this sort of gooey gushiness doesn't really suit the down-to-earth Hannigan at all. She comes across as a very old-fashioned spirit, someone who loves "arts and crafts" and someone who took great pleasure in hand-producing the lyrics on Sea Sew.

"My mother knitted the cover for me and I knitted the lyrics," she says. "I love that kind of stuff; I love embroidery and craft and to make a real thing."

This earnest country girl's blog is also noted for containing recipes for baking cakes, and on Dermot O'Leary's show she went into detail about her method for cooking the perfect roast potato. Frankly, Hannigan comes across like a character from a Maeve Binchy novel, and her childhood sounds blissful.

"County Meath was mad rural, full of nature and idle play, playing with sticks and stuff," she says. "We'd go into Dublin and it would be quite a big trip into town.

"I was a nerd," she adds. "And I mean that in the best possible sense – I certainly wouldn't use that as a pejorative term. Nerds unite! I like reading and nosing around things."

She also confesses that, when she was tiny, she had a small gang and her superpower in the gang was that she would bring snacks. "My codename was Oxo. I used to bring this brown lumpy rock sugar and we would sit there sucking on the sugar, thinking of ways to annoy the neighbours. I was only three."

This sweetness is echoed in her lyrics (as on "Lille" where she exclaims "We went out to play for the evening/And wanted to hold on to the feeling/And the stretch in the sun/And the breathlessness as we run"). But her words are not something she's not terribly keen to discuss in detail: "I do like writing about the mundane details of daily life, but I don't tend to analyse it too much."

There is, however, a nice stream-of-consciousness feel to some of her songs, as on "I Don't Know": "I'd like to meet you/I don't know if you drive/If you love the ground beneath you/I don't know if you write letters or panic on the phone."

"On iTunes my music is labelled as alternative, which I'm quite happy with," she admits. "You couldn't call it pop or rock really. Alternative is a giant umbrella I can shelter under, you know. In fact, my friends call my music plinky-plonk rock, which I quite like. I'm pretty much at the forefront of plinky-plonk rock," she laughs.

Her material, such as the sumptuous "Lille" and "Ocean and a Rock", is redolent of Kristin Hersh (she was "obsessed" by her 1996 album Your Ghost and "played it to death"), Edie Brickell (she does a droll imitation of the hit "What I Am") and has a whiff of All About Eve. And, unsurprisingly, Joni Mitchell.

"I know every word of Ladies of the Canyon," she says. "Joni Mitchell does such a breadth of creative things. She's such an amazing artist."

Hannigan, who also adores opera, W B Yeats, Dylan Thomas, Sidney Lumet's film 12 Angry Men, and has soft spot for The Lord of the Rings and Harry Potter, craves to be a substantial artist and experiments with a raft of instruments and sounds on Sea Saw.

"I like the glockenspiel and the harmonia," she says. "I like the nostalgic, squeeze-box sound, and its shimmery brightness."

Expect Hannigan's star to keep on shining brightly. Her lovely voice will appear on Neil Jordan's new film,

Ondine, starring Colin Farrell and Stephen Rea, out soon. "Neil Jordan needed a song for a wedding scene, a really romantic song, so I sang 'Lille'," she says, rather matter of factly. "When a song works on a soundtrack it's brilliant. When it works, it makes everything bigger and the drama larger."

Hannigan turns her attention back to the pigeon, before our chat is terminated by her people. She's a bit of an enigma, this acoustic crooner, and a very reasonable outside chance at 6-1 for the Mercury prize. I'll wager Damien Rice doesn't feel so clever now...

The Mercury prize ceremony takes place on Tuesday 8 September