The Romans, who called Ireland ‘Hibernica’ after Winter, clearly never visited the place. Compared with northern France, Germany or, for that matter, guard duty on Hadrian’s Wall, Ireland’s climate is soft, if moist. True, the Roman armour might have rusted, but their gardens would have flourished. The Venerable Bede found Ireland a land of milk and honey ‘with no lack of vines’. Not far off paradise, in short.

The inhabitants knew this, we learn, whether Iron Age Celts who listed their native plants as though they were in social classes chiefs, commoners and peasants or monks at the Cistercian monastery at Corcomroe who, in 1205, created the West’s first botanical carvings. In 1692, Sir Arthur Rawdon of Moira sent his gardener to Jamaica to collect exotic trees, while 30 years after that, Dublin University’s physic garden grew plants from Africa.

The 20 gardens in Olda FitzGerald’s striking book date fromKillruddery, where, in 1684, the 4th Earl of Meath employed French designer Monsieur Bonet to create a garden inspired by Versailles, to Butterstream, created single-handedly from a field by Jim Reynolds, an archaeologist.

Along the way she introduces us to some splendid characters: Henry McIlhenny, the American inventor of gas meters, ‘who treated his plants like guests at a cocktail party’, and Annan Bryce who got Harold Peto to design the island garden of Ilnacullin as if it were in the Bay of Naples. Then, at Altamount, there was Corona North (named after her father’s favourite rhododendron), who travelled the world to find beautiful trees. ‘A statuesque figure with turquoise blue eyes’, she could be telephoned only when it was too darkto mow the lawns.

If you thought that the author often strays from strict garden information you would be right. We hear of her husband’s ancestors, the ‘Cracked’ Knight of Glin who rode his horse up stairs and the ‘Big’ Knight who sank a bottle of whiskey a day. But what are gardens without their creators? Madame FitzGerald writes with deep knowledge of both the plants and the people who made these lush retreats. The photographs by Stephen Robson and the excellent garden plans by William Pounds do her text full justice. Sad to say, however, the proof-reading is sloppy and the captions uninformative. Still, the book is as exciting as the views at Birr, as tasty as the vegetable garden at Creagh and as eccentric as the Dodo terrace at Mount Stewart.