Frances Tophill is back at Powderham Castle in Devon, where she puts the finishing touches to a new herb area. She prepares the vegetable beds for winter, planning for spring colour by planting tulip bulbs and demonstrating how to easily identify and remove common garden weeds. Seed collection is the focus for Carol Klein as she concludes her mission to get people growing plants for free. Rachel de Thame continues to explore the ingenious power that flowers use to attract pollinating insects. While a soil expert uncovers the mysteries of a universe hidden beneath the earth and explains why the minute beasts that thrive there are so vital for gardens.