A vertical garden standing at 21 metres tall has recently emerged in Victoria, London. The permanent garden that contains over 10,000 plants and 16 tonnes of soil covers the facade of The Rubens at the Palace hotel. The living wall that covers 350 square metres of the road-facing side of the luxury hotel, was designed by Gary Grant of Green Roof Consultancy to reduce local environmental issues such as flooding and air pollution.

The living wall is a direct result of the Victoria Business Improvement District audit that was carried out in 2010 and led by environmental and sustainability manager David Beamont, to identify new locations for green space that would most benefit people and wildlife.

The garden is maintained by a sustainable drainage system whereas living walls have been criticised in the past for using filtered water.  It is irrigated by harvested rainwater that is captured by storage tanks on the building’s roof and is slowly channeled through to the plants. According to Beamont, this will reduce surface water flooding in the immediate area.

“It’s a 350-square-meter green sponge,” explains Beamont, adding that “the plants themselves will take up rain too, so the rain doesn’t fall on the street below.”

As well as soaking up excess rain water, the garden will also serve as an air-pollution cleaner.

“Vegetation can trap microscopic pollutants known as particulate matter, high levels of which have been shown to cause respiratory illnesses. Vegetation can also disperse heat more generally so [living] walls help to reduce local air temperatures and tackle the urban heat island effect.”

The variety of plants including native ferns, English ivy, strawberry, primroses and geraniums have been recommended by The Royal Horticultural Society as the best pollinators.

 “My approach is to use native species in natural associations, however sometimes it’s not practicable because of problems with availability or a lack of visual interest or late flowering,” he says. “It’s still necessary to choose plants that are known to thrive in living walls, or are likely to thrive in living walls, and are suited to the aspect and microclimate.”