Start with a trip to the Powerscourt Gardens in County Wicklow, at the foot of the looming Great Sugar Loaf Mountain. These captivating gardens are among the most impressive in Europe, with giant sequoias and dwarf copper chestnuts jostling for space with azaleas, magnolia and rhododendrons. And there’s even a pet cemetery!Down the road on the banks of the Vartry River lies Mount Usher at Ashford, with exotic flowers from around the globe, truly spectacular magnolias in spring, trees and shrubs and a beautifully classic rose garden. Continue the tour in the smallest county in Ireland, Carlow. The Altamont Gardens near the village of Ballon is a fascinating collection of ornamental gardens and lakeside walks with soaring redwood trees and the atmospheric multi-coloured Chinese dawn redwood. Finish off your tour by heading south to the village of Clonegal and the magnificent Huntington Castle. Part of an ancient hallowed site, nearby is a little Neolithic stone, used in pre-Celtic times for healing, and the River Slaney, known as the river of healing. The castle itself is located at what’s known as the Crow's Foot, the confluence of the River Slaney and the River Derry, named after the druid oak.