The flagpole at Kew Gardens, which stood from 1959 until 2007
Kew consists mainly of the gardens themselves and a small surrounding community. Royal residences in the area which would later influence the layout and construction of the gardens began in 1299 when Edward I moved his court to a manor house in neighbouring Richmond (then called Sheen). That manor house was later abandoned; however, Henry VII built Sheen Palace in 1501, which, under the name Richmond Palace, became a permanent royal residence for Henry VII. Around the start of the 16th century courtiers attending Richmond Palace settled in Kew and built large houses. Early royal residences at Kew included Mary Tudor's house, which was in existence by 1522 when a driveway was built to connect it to the palace at Richmond. Around 1600, the land that would become the gardens was known as Kew Field, a large field strip farmed by one of the new private estates.
The exotic garden at Kew Park, formed by Henry, Lord Capell of Tewkesbury, was enlarged and extended by Augusta, Dowager Princess of Wales, the widow of Frederick, Prince of Wales. The origins of Kew Gardens can be traced to the merging of the royal estates of Richmond and Kew in 1772. William Chambers built several garden structures, including the lofty Chinese pagoda built in 1761 which still remains. George III enriched the gardens, aided by William Aiton and Sir Joseph Banks. The old Kew Park (by then renamed the White House), was demolished in 1802. The "Dutch House" adjoining was purchased by George III in 1781 as a nursery for the royal children. It is a plain brick structure now known as Kew Palace.
The Epicure's Almanack reports an anecdote of the garden wall as of 1815: "In going up Dreary Lane that leads to Richmond you pass along the east boundary wall of Kew Gardens, extending more than a mile in length. This dead wall used to have a most teazing and tedious effect on the eye of a pedestrian; but a poor mendicant crippled seaman, some years ago, enlivened it by drawing on it, in chalk, every man of war in the British navy. He returns annually to the spot to refit his ships, and raises considerable supplies for his own victualling board from the gratuities of the charitable, who pass to and from Richmond."
Some early plants came from the walled garden established by William Coys at Stubbers in North Ockendon. The collections grew somewhat haphazardly until the appointment of the first collector, Francis Masson, in 1771. Capability Brown, who became England's most renowned landscape architect, applied for the position of master gardener at Kew, and was rejected.
In 1840 the gardens were adopted as a national botanical garden, in large part due to the efforts of the Royal Horticultural Society and its president William Cavendish. Under Kew's director, William Hooker, the gardens were increased to 30 hectares (75 acres) and the pleasure grounds, or arboretum, extended to 109 hectares (270 acres), and later to its present size of 121 hectares (300 acres). The first curator was John Smith.
The Palm House was built by architect Decimus Burton and iron-maker Richard Turner between 1844 and 1848, and was the first large-scale structural use of wrought iron. It is considered "the world's most important surviving Victorian glass and iron structure". The structure's panes of glass are all hand-blown. The Temperate House, which is twice as large as the Palm House, followed later in the 19th century. It is now the largest Victorian glasshouse in existence. Kew was the location of the successful effort in the 19th century to propagate rubber trees for cultivation outside South America.
In February 1913, the Tea House was burned down by suffragettes Olive Wharry and Lilian Lenton during a series of arson attacks in London.
Kew Gardens lost hundreds of trees in the Great Storm of 1987.
From 1959 to 2007 Kew Gardens had the tallest flagpole in Britain. Made from a single Douglas-fir from Canada, it was given to mark both the centenary of the Canadian Province of British Columbia and the bicentenary of Kew Gardens. The flagpole was removed after damage by weather and woodpeckers made it a danger.
In July 2003, the gardens were put on the UNESCO list of World Heritage Sites by UNESCO.
A five-year, £41 million revamp of the Temperate House was completed in May 2018.
Five trees survive from the establishment of the botanical gardens in 1762. Together they are known as the 'Five Lions' and consist of: a ginkgo (Ginkgo biloba), a pagoda tree, or scholar tree (Styphnolobium japonicum), an oriental plane (Platanus orientalis), a black locust, or false acacia (Robinia pseudoacacia), and a Caucasian elm or zelkova (Zelkova carpinifolia).