The landscape architects designed the newly opened canary Wharf Crossrail roof garden, which is under a semi-open air timber lattice roof from Foster + Partners.
Blakedown Landscapes is the contractor and has the maintenance contract.
Load bearing is one of the main challenges for roof garden designers, along with access to build them. The 1.5m garden base includes lightweight fibrous soil, waterproofing, insulation and a "big tray" for planting.
The roof is 310m long and features 780 EFTE pillows continually filled with air.
Richards adds that Canary Wharf and the Walkie Talkie "are at the upper end of ambition" but "show you can do it. All developers we're working with are interested in the benefits of access to green space."
He says the current New London Architecture Public London exhibition is full of sky garden plans.