The plantswoman and broadcaster visits Gresgarth Hall, the Lancashire country home of garden designer Arabella Lennox-Boyd. The grounds of the estate comprise the formal garden rooms nearer the house, and a wilder area where Arabella has planted 6,000 trees among cleverly designed meandering paths. Elsewhere, the garden shows off Arabella's immense knowledge and precision. In spring, splashes of early colour nestle beneath well-chosen spring-flowering shrubs, while summer witnesses an explosion of scent and floral abundance.