Christine Walkden's airborne adventure takes her to Cornwall. At the tropical paradise that is Trebah Garden she's transported back to childhood by the giant Brazilian gunnera and meets Marcus, whose own childhood was spent playing in the garden. Her nerves are tested at St Michael's Mount when she comes face to face with gardening on the edge. And we meet the oldest member of one of Cornwall's oldest male-voice choirs.

Christine Walkden continues her airborne exploration of Britain's gardens by dropping in on the county of Essex. At the Beth Chatto Gardens, Christine experiments with triangular planting and shares tea and cake with a gardening legend. At RHS Hyde Hall, she shifts rocks with a former student, and it's all aboard a vintage Thames sailing barge for a trip on the Blackwater Estuary.

Mid-Wales is today's destination on Christine Walkden's balloon tour of some of Britain's finest gardens. At Powis Castle Garden, she learns how to brace an ancient yew and meets David, generations of whose family worked there. At the Dingle Garden she helps restore an obscured view. And we hear the story of Mona Holloway, a wartime land girl who found love on a neighbouring farm.