Victoria Business Improvement District aims to bolster "green infrastructure" in the streets and squares of the south London area.
Monthly audits will be carried out across the Westminster zone to ensure areas look their best for the residents, workers and tourists.
Initiatives include removing signage clutter and projects to reduce carbon emissions, said chief executive Ruth Dutson.
Desk plants will be given to office workers, while more trees and shrubs will go into streetscapes. The group will also explore how green infrastructure could potentially help to bring down inner-city temperatures and reduce carbon footprints.