Diarmuid and Helen encounter an astonishing mixed bag of great private gardens in County Down. First off, on the banks of Strangford Lough, they visit a large estate containing a 200-year-old walled garden. Their next destination is an eccentric garden dominated by alpine rock plants, behind a modest house in Bessbrook. Finally, they visit Castlewellan, where they encounter a mature garden peppered with lots of comic touches.