The gardens in Kensington Gardens Square were created in 1876 for the private use of the residents, the then-emerging professional classes. The communal garden continues to be for the private use of residents of the surrounding houses.
Like many garden squares in London, the railings were removed during WWII as part of the war effort, with the intention being to melt down the metal for use in weapons manufacture. The majority of metal seized, however, was never melted down and was instead thrown into the Thames off Sheerness on the Isle of Sheppey when it was realised that repurposing the metal would be costly and impractical. More information on this topic can be found here. Some of the railings have been replaced with replica wrought-iron railings as part of the upgrading of the gardens.
The gardens are largely lawn, with shrubs and a perimeter path; among the trees are a number of fine London planes.