The square takes its name from Eccleston in Cheshire, part of the estates owned by the Duke of Westminster. Originally a low-lying swamp which was drained in the early 17th century, it was planned as a three-acre square in 1828 by Thomas Cubitt (1788– 1855). Over the past 30 years, the whole garden has been replanted to give year-round interest. There are many specialist collections, including camellias, climbing and shrub roses, and a National Collection of ceanothus. In 2006, a Wollemi pine – thought to have been extinct until found recently in Australia – was donated to the square. Other unusual tender plants in the garden include specimens of the giant Mexican dahlia, Dahlia imperialis, and the white sunflower tree, Rojasianthe superba, from Guatemala.