In an hour long Christmas edition of Gardeners' World, Monty Don, Carol Klein, Joe Swift, Sarah Raven and Alys Fowler offer 12 gardening ideas to cover each of the 12 days of Christmas. Carol and Joe enjoy a series of winter walks with a horticultural flavour. Sarah follows the journey of the British cobnut from harvest to the plate. Back at Berryfields, Monty and Alys tackle a host of winter tasks and start planning the new gardening year.