There’s a whole lotta love between Patty Griffin and Robert Plant. So much so – if certain stories are to be believed – that the twosome have already tied the knot! But as the American singer-songwriter is quick to state (and not for the first time), it’s nothing but a rumour.

“No. We’re not married,” she reconfirms politely, adding the ongoing media interest in her relationship with the former Led Zep frontman continues to perplex them both.

“We’re both really private people,” she says of their unexpected “celebrity couple” status. “And I would have thought we were a little too old for people to care!”

The two met when producer Buddy Miller called on her vocal services for Robert Plant’s 2010 Band Of Joy album, soon joining Plant’s live touring band.

“It was a good time to do that. I’d been pushing really hard for a long time. I wasn’t out of gas, but I needed a change of scenery,” she says of her decision to swap her solo career for that of a backing band member.

“It was really a great time, just being a singer, you’re not entertaining the audience, that’s not your job, that’s Robert’s job. I put my heart and soul into my part and it was nice to be on stage with someone who has to do the other stuff. And he does it so well.”

But now Patty’s back centre-stage with her seventh album, American Kid, a collection of powerful, emotional and stark songs that often delve “unapologetically” into the darker side of life.

“There is a common thread running through it,” she says of the album. “The songs were written at the time when my father was passing away. I was digging into his life and wanted to find out more about him, and he was not in a situation where he could tell me much. Some of the songs are these stories about him, and some of which are complete fiction – I made stuff up. And that coincided with the United States’ involvement in Afghanistan and Middle East, and a government that’s not for the people.”

Robert Plant performs with Patty Griffin
Robert Plant performs with Patty Griffin

A former science teacher who fought in the Second World War and lived, for a time, in a Trappist monastery, Mr Griffin kick-started his young daughter’s love of music by buying her The Beatles’ Sgt Pepper album.

“I was examining my father’s life, from day one until the last day, and looking at the changes that took place over his life, and it was an unrecognisable place to him in the end – not because of reasons of dementia, but because he could not get what had happened. He felt a lot of disappointment, and so the songs were written with that perspective.”

Another influence on the material was Patty’s experience with Band Of Joy (with BoJ’s Mr Plant lending his vocal tones to three tracks: Ohio, Faithful Son and Highway Song).

“Some of the old adventurousness of my youth has been summoned back,” she laughs. “Being in Band Of Joy kicked my butt, I had to step up the plate, playing guitar and following a singer around with my voice. I was landing on notes I didn’t know I could hit!”

But with Band Of Joy now, temporarily at least, history, Patty’s relishing the prospect of heading out on her own.

“I really love that solo journey, that folk singer thing. There’s much more freedom for me. You can arrange a song on the spot, change a song,” she says.

With Mr Plant living just down the road, can we expect him to make an appearance at Patty’s forthcoming Birmingham show?

“I wish,” she smiles. “But he’s on tour in the United States at the same time.”

* Patty Griffin plays Glee Club, Birmingham, on July 24. Tel: 0871 472 0400 or visit www.glee.co.uk/birmingham