Two sides of the flytower of Britain's National Theatre were grassed in May 2007. The project was conceived and executed by British artists Heather Ackroyd and Dan Harvey who, needless to say, love grass. They see the work as a comment on growth, decay and global warming. The grass will be allowed to turn yellow and die, after the photographs below were taken, to show what global warming might do the Earth.
The work was carried out by a team of 20 workers. They smeared 2.5 tons of clay over the concrete, achieving a depth of 4-5mm and then pushed grass seedlings into the damp clay. It receives some water from the Good Lord above and some from gardeners who walk on top the building with hoses. But the man on the lower left picture is not a gardener. He is part of Anthony Gormley's Event Horizon, an installation of 31 sculptures. They are casts of the artist's naked body, placed on rooftops and pedestrian areas on and around around the South Bank.