A look at the palace and gardens of Parque de Monserrat in the Portuguese town of Sintra, which span 80 acres and are a testament to the Victorian era's adventurous spirit of plant collecting. Featuring the sun-soaked Mexican garden, where towering cacti and vibrant blooms create a dazzling spectacle, and Fern Valley, a shaded paradise alive with lush tree ferns from Australia and New Zealand

A look at Trsteno Arboretum in southern Croatia, which is perched on a limestone cliff and boasts a rich history that spans more than 500 years. The programme uncovers its opulent Renaissance origins, featuring ancient stone columns, sprawling ornamental trees, sun-drenched citrus groves and intricately designed maze-like shrubs.