This is a curious book. Its subtitle suggests that we are in for a bit of rumination, and we get plenty, but as I read I found myself increasingly perplexed, wondering if Richard Mabey had quite decided what the book was supposed to be.

The facts are simple enough: visionary Dutchman Tim Smit, who reclaimed the skeletal remains of the gardens at Heligan in Cornwall from decades of neglect and brought a horticultural past to life, created transparent biomes, seemingly made out of giant sheets of bubble wrap, in a disused quarry not far away to house collections of plants and trees from around the globe, and made it into one of the must-see attractions of south-west England; 1.4 million people visit it each year.

Richard Mabey is a distinguished and much-loved nature writer. But Fencing Paradise is frustrating for its peripatetic approach to its subject, as if the book were a sort of potted ‘Further Reading’ for those who have viewed the site and want to cogitate a little more deeply on its meaning.