The `It`s Complicated` star plays in bluegrass band SteveMartin and The Steep Canyon Rangers and he has to have false nails fitted every few weeks because the banjo has damaged his fingers.
He explained: "The last time I got false nails was two weeks ago. My real nails got torn up from playing. It`s a typical thing to have false nails in bluegrass. You go into any beauty parlour and say, `I need acrylic nails on the first two fingers please.` And they ask if you`re a guitar player. I have them re-done every two or three weeks. I like to wait for them to fall off before I get a fresh. Have I ever been tempted to paint them? I have not."
The 65-year-old actor has been playing the banjo since he was 16 and he insists he prefers the instrument to its six-stringed cousin, the guitar.
He told Q magazine: "From where I`m sitting I can see four banjos. As soon as I`m finished this interview I`ll pick one up. I play every day. But a banjo weighs about 20 pounds, whereas a guitar weighs about five, so I couldn`t pick it up and still hold a phone and talk."