THE GARDEN AT PEN MILL FARM, TUCKED into a quiet corner of south Somerset near Wincanton, benefits from the same fertile, acid greensand soil that fuels Stourhead, just across the county boundary in Wiltshire. “The growing conditions are wonderful, though there is a sticky clay below the greensand and springs pop up all over the place,” says Sarah FitzGerald, who has gardened here for 30 years since taking on the farm with her husband, Peter, from his parents.
Surrounded by views of woods and farmland, and watered by a tributary of the nearby River Stour, Pen Mill Farm benefits from natural assets that Sarah and her predecessors have been careful not to spoil. “With a site like this we couldn’t impose a formal layout, so we compromised by introducing…