A complex of two residential towers – one standing 110 metres high, the other 76 metres high – the Bosco Verticale, or “Vertical Forest”, is located in the centre of Milan at the edge of the Isola district. The design is distinguished by its 900 trees, over 20,000 plants and a wide range of shrubs and flowers arranged vertically on its facades. For this reason, it is described as a model for the vertical densification of urban nature. These Milanese towers are therefore the first example built with the express aim of reforesting the city to aid environmental regeneration and urban biodiversity without extending the city further into the surrounding land. 
The trees (of 3, 6 or 9 metres high) were planted in relation to the facades’ orientation towards the sun. Tree species were selected in order to adapt their positioning on the facades, also allowing for their height. The plants were expressly pre-cultivated in a specialised nursery.
The management of the tubs that contain the trees is based on building regulations, along with the maintenance of the greenery and the number of plants allocated to each apartment. To calculate and satisfy the water needs of the vegetation, the design also considered the distribution and positioning of the various species on the towers.