Ever since their discovery, carnivorous plants have fascinated scientists and spurred the imagination of artists, writers and filmmakers. While the Puya chilensis cactus at the Royal Horticultural Society Garden in Wisley, Surrey, that recently blossomed for the first time in 15 years has been breathlessly reported as a “sheep-eating” cactus (they are merely entangled in its velcro-like spines), the reality of carnivorous plants is often considerably stranger than fiction.