As the Cherwell River skirts past Christchurch meadows, the familiar skyline of Oxford comes to a gentle halt. Limestone University facades give way to a lattice of steel and glass, where flaxen church spires morph into fierce talons of cacti. Beyond, an ochre archway frames a pair of Chinese windmill palms, beneath which a gaggle of lemon trees bask outdoors for the summer.

No ordinary garden is this, but the untold oasis of Oxford’s Botanic Garden. Extending across five acres, this unique sanctuary spans walled gardens, herbaceous borders and vegetable beds, not omitting lily ponds, a wild flower meadow and rockery. All in the company of 18th century glasshouses, offering both a cosseted respite from the British weather and miraculous journey through seven diverse habitats - from jungle to swamp, arid desert to alpine pasture.