Lily Cole is mixing charity work with knitting for a campaign with Innocent Smoothies.

The flame-haired supermodel is wrapping up warm for the 'Big Knit', now in its 10th year, which raises money for Age UK.

The nation's grannies have been twiddling their knitting needles making hats for smoothie bottles while Innocent has teamed up with North Circular to create adult-sized beanies, which will be sold in supermarkets across the UK from November 6 to 29.

For each wool hat sold, 25p will go to the charity helping elderly people that suffer during Britain's cold winters.

Lily, 25, who has modelled for the likes of Chanel and Louis Vuitton, has been involved in a number of high-profile charity campaigns in recent years and supports a number of humanitarian and environmental causes.

She also joined a campaign earlier this year to save a billion trees in the rainforest.

She said at the time: ''I'm not like some cliché hippy, but I really love trees and I love nature. And that appreciation has grown as I've got older.''

Lily modelled a T-shirt with the slogan 'Save the Future' to fight child labour in the fashion industry for the Environmental Justice Foundation, and opened Vivienne Westwood's show at London Fashion Week with a solo dance to raise awareness about climate change.

Each beanie made for the Big Knit campaign can be bought from the start of November at www.thenorthcircular.com.