Ventnor Botanic Garden is a botanic garden located in Ventnor, Isle of Wight. It was founded in 1970, by Sir Harold Hillier, and donated to the Isle of Wight Council.
Its collection comprises worldwide temperate and subtropical trees and shrubs organised by region. The garden’s unusual climate is more akin to the Mediterranean and enables a wide variety of plants considered too tender for much of mainland Britain to be grown. These grow in the open air, and benefit from the moist and sheltered microclimate of the south-facing Undercliff landslip area on the Isle of Wight coast. When frost does occur it is usually of short duration and not of great severity.
The garden is on the site of the Royal National Hospital for Diseases of the Chest, a sanatorium established there to exploit the same mild climate. Founded by Arthur Hill Hassall, designed by local architect Thomas Hellyer and opened in 1869 as the National Cottage Hospital for Consumption and Diseases of the Chest, it offered 130 separate south-facing bedrooms for its patients. The hospital closed in 1964, made obsolete by drug treatment of tuberculosis, and demolished in 1969.