An extended edition sees Monty Don add autumn perennials to his borders, show how to take root cuttings and reveal plans for next year when he plants bulbs for spring colour. On her Kent allotment, Frances Tophill catches up on some seasonal sowing and invites a special guest to help her with a small building project. Nick Bailey visits Cambridge University Botanic Garden, where he finds out how and why some plants produce their scent at the end of the day. The programme also returns to the wildlife garden of Kate Bradbury to find out about the lives of solitary bees.