The country girl who met the Led Zep legend

James McNair meets Alison Krauss

On the mic: Alison Krauss (REUTERS)

Backstage at The Sage, Gateshead, the phrase "hobnobbing with the stars" has taken on a different meaning. The McVitie's biscuit of the same name is much loved by Alison Krauss, and a pack is brightening the singer's day post-sound check.

Such simple pleasures seem curiously typical of this 26-time Grammy award winner and reigning bluegrass queen, a woman who is, by all accounts, very low-maintenance. Warm but wary, sans make-up, and dressed in a tomboyish, decidedly off-stage outfit of purple sweatshirt, jogging pants and trainers, Krauss deflects compliments and describes herself as, "a bit of a hermit; someone a little out of step with the modern world".

Presumably her bandmates fussed over her when she turned 40 on tour back in July? "Oh no!" she says, pulling a goofy appalled-at-the-idea face. "I'm not a big party person and I wouldn't want them walking onstage with a cake..."

My interviewee's distinct lack of diva syndrome reportedly impressed Robert Plant when the pair duetted on 2008's two-and-a-half million-selling album Raising Sand, but Krauss's impeccable bluegrass pedigree was doubtless a draw, too. Signed to esteemed roots-music imprint Rounder Records when she was 14, this gifted Illinois-born fiddler and singer had a residency at the Grand Ole Opry by the time she was 21. When T-Bone Burnett came to produce the soundtrack for the bluegrass-fuelled comedy film O Brother, Where Art Thou?, Krauss was a trusted contributor and consultant. Another O Brother session player, the singer and guitarist Dan Tyminski, continues to co-front Krauss's band Union Station and she jokingly introduces him as "the voice of George Clooney" at gigs.

Between them Krauss and Tyminski have probably done more to propagate bluegrass than anyone since the inventor of the banjo. But after all these years, what is it that brings Krauss back to the well? "I just love the message", she says, pulling at tousled blonde locks. "It's a fantasy about simple life and basic values and there's not too much psychology or over-thinking things. It's 'one woman and only this woman', you know? It's, 'I believe this and only this'. It's, 'I killed this person and I should have', or 'I killed that person and I shouldn't have'. It's very black and white and I love the picture it paints about home and family." But for her it's just a fantasy?

"Well, when I say fantasy, I don't mean that it isn't truthful," the singer qualifies. "When I listen to Charlie Louvin's music I hear about the hard times in life and the beautiful times. It rings true and I can get lost in it."

It's well known that the singer brought up her son Sam (now 12) as a single mum, having divorced from his bluegrass musician father Patrick Bergeson in 2001, but Krauss and those around her guard her privacy closely, and if she has dated anyone since Bergeson, names are not something search engines proffer.

One of the key tracks on Paper Airplane, the fine but unrelentingly melancholic 2011 album that Krauss's UK tour is promoting, is her take on Richard Thompson's 1973 ballad, "Dimming of the Day". First sung by his wife Linda while the couple were going through a divorce, it's a song that has resonance for Krauss. So much so, in fact, that she declined to sing it on Jools Holland's Later earlier this year for fear she might break down.

"Goodbye is All We Have"; "Ghost in This House"; "Too Late To Cry" – Krauss's back catalogue is riddled with heartache, while part of Paper Airplane's title track runs: "Every silver lining always seems to have a cloud/ That comes my way." That old joke that, if you play a country record backwards, the crop doesn't fail, your dog doesn't die, and your partner doesn't leave you, reminds us of the genre's pact with adversity. Still, if you're hurting, doesn't singing country aggravate matters?

"When I'm singing those songs and I relate to them it's not tortuous," says Krauss. "It's a healing thing. I think that people respond to honesty in music, so I only choose songs that are the truth for me."

Alison Krauss and Union Station play the Royal Festival Hall, London SE1 (020 7960 4200) 12 to 15 November