Rocker Neil Young has given up drugs and alcohol for good after puffing marijuana and knocking back alcohol for years.

The Harvest Moon hitmaker retired both his bad habits last year (11) and is now celebrating his sobriety.

He tells the New York Times, "I did it for 40 years. Now I want to see what it's like to not do it. It's just a different perspective."

But the 66 year old insists it has been no easy feat - in his upcoming memoir, Waging Heavy Peace, he writes, "The straighter I am, the more alert I am, the less I know myself and the harder it is to recognise myself.

"I need a little grounding in something and I am looking for it everywhere."