Bosco Verticale: a vertical forest in the middle of Milan’s urban jungle

4 min read

Bosco Verticale is a unique residential complex in the city center of Milan, Italy. It consists of two towers that stand 80 and 112 meters high and are covered in plants and trees giving them the look that inspired their name, vertical forest.
The project was proposed by architect Stefano Boeri as part of his BioMilano: six ideas for a bio-diverse metropolis. His firm, Boeri Studio, describes the towers as “a model for a sustainable residential building, a project for metropolitan reforestation that contributes to the regeneration of the environment and urban biodiversity“, and “it was designed as a home for trees that also houses humans and birds“.
According to Stefano Boeri, the building was inspired by Italo Calvino’s 1957 novel The Baron in the Trees, in which the protagonist decides to abandon the ground and live in the trees for the rest of his life.

It was inaugurated in October 2014, in Milan’s Porta Nuova Isola area, as part of a wider renovation project. The complex, called “the most exciting new tower in the world,” comprises two 27-story residential high-rises teeming with cantilevered balconies and planted with almost 900 trees and more than 2,000 shrubs and bushes.
That amounts to 30,000 square meters of woodland and undergrowth, concentrated on 3,000 square meters of urban surface. And the vegetation is not just for show.

“Unlike ‘mineral’ facades in glass or stone, the plant-based shield does not reflect or magnify the sun’s rays, but filters them thereby creating a welcoming internal microclimate without harmful effects on the environment,” the Boeri Studio website reads.
“At the same time, the green curtain ‘regulates’ humidity, produces oxygen and absorbs CO2and microparticles, a combination of characteristics that have brought the project a number of important awards.”
That sounds like the marketing-oriented description an architecture studio would use to promote its work, but in the case of Bosco Verticale, these claims are backed by the testimonies of residents who have lived in these two towers for years.
CNBC recently ran a piece on this unique residential development and learned that the vegetation has a positive effect on residents in more ways than one.
“I’ve been living at the Bosco Verticale since its opening,” a resident told. “It doesn’t feel like we’re living right in the middle of busy Milan, where everything goes quite fast. Having these plants right on the terrace, real trees, has certainly had a positive impact on my life,” she added. “It brings the temperature down in the summer and it feels like these plants have generated a microclimate, it’s very pleasant. In the winter, we use less heating thanks to this greenhouse effect and in the summer, we use less air conditioning because the air is cooler.” The buildings are also equipped with solar panels and a gray water recycling and irrigation system.

This concept certainly isn’t the new, in fact several similar buildings was built in the past, including Edificio Santalaia, a plant-covered building in the middle of Bogota, Colombia, or the Qiyi City Forest Garden residential complex in Chengdu, China.
But they’re not all success stories. For example, the the Qiyi City Forest Garden recently made international news headlines after becoming a mosquito-infected, unkept jungle. So how does Bosco Verticale maintain its pristine look?
Apparently it’s thanks to the “Flying Gardeners”, a specialized team of arborists-climbers who, once a year , descend from the roof of the two towers, using mountaineering techniques, to carry out pruning, routine maintenance, or any necessary substitution on the plants. Irrigation is centralized, with the plants being constantly monitored by a digital and automated system.
Either way, a few years after its inauguration, Milan’s Bosco Verticale also became home to a number of animals insects, including about 1,600 specimens of birds and butterflies, all of which live in harmony with the human inhabitants.