The Royal Horticultural Society's garden at Wisley in the English County of Surrey, South of London, is one of four gardens run by the Society - the others being Harlow Carr, Hyde Hall and Rosemoor. Wisley is the second most visited paid entry garden in the United Kingdom after the Royal Botanic Gardens, Kew, with nearly a million visitors each year.

Wisley was founded by Victorian businessman and RHS member George Ferguson Wilson, who purchased a 60-acre site in 1878. He established the "Oakwood Experimental Garden" on part of the site, where he attempted to "make difficult plants grow successfully". Wilson died in 1902 and Oakwood (which was also known as Glebe Farm was purchased by Sir Thomas Hanbury, the creator of the celebrated garden La Mortola on the Italian Riviera. He donated both sites to the RHS in the following year.