In 1772, King George III inherited the Kew estate, and joined it with the royal estate in Richmond. Him doing this turned the Royal Botanic Garden of Kew into multiple gardens, making it the Royal Botanic Gardens of Kew

King George III is the monarch that most strongly associated with the Kew estate, especially since he spent much of his childhood there. In adulthood, he supported the development of the Royal Botanic Gardens of Kew. In fact, later in his life, George often exchanged ideas with multiple botanists, horticulturalists, and explorers, and he encouraged their innovations. King George III's interest in agricultural developments earned him the nickname 'Farmer George.'

www.hrp.org.uk: Kew Palace & George III, The Mind Behind The Myth

www.kew.org: Kew Gardens Surprising Historical Facts

www.hrp.org.uk: George III