Bosco Verticale, The Forest Living In A Milan Highrise

Bosco Verticale at sunset
Bosco Verticale at sunset
Britta Nagel

MILAN — The International Highrise Award enjoys great prestige because, unlike other similar competitions, it is granted neither for a building's height nor form. Instead, the prize — bestowed by the German Architecture Museum, the city of Frankfurt and Deka Bank — honors criteria such as sustainability and innovation. And this year's winner, Milan's Bosco Verticale (Vertical Woods), has that in spades.

The 2014 jury, led by architect Christoph Ingenhoven, cited Italian architect Stefano Boeri's work for its environmental ambitions in difficult circumstances. Piazza Gae Aulenti, in an area of new construction around Porta Garibaldi, is Milan's ugliest square. The huge urban space on the northern edge of the historic city center is virtually empty of people at night. With its skyscrapers and buildings of international companies that are present in every large city in the world, it looks like something between Berlin's Potsdamer Platz and the Dubai Mall.

Only a closer look reveals something unusual behind Italy's tallest building, the Torre Unicredit by César Pelli: two black towers of differing heights with 100 white balconies that look like pulled-out drawers.

The towers, which were completed a little over a month ago, are somewhat reminiscent of the women's opened drawers in Salvador Dalí"s The Burning Giraffe. But just how right it is that the buildings have been baptized the Bosco Verticale is only perceptible from up close.

Unlike the imagery in the project's prospectus, the vegetation on the balconies is still far from jungle-like. But vegetation there is, and it is so impressive that hordes of tourists come here to take pictures of the towers.

"The Bosco Verticale is a worldwide unique architectural experiment, a model for future inner cities," says its architect, 57-year-old Stefano Boeri. He hails from an influential local family, was an urban planner for many years, and ran for mayor of Milan two years ago.

It's only on the 25th floor of the higher of the two towers, which are 110 and 76 meters high respectively, that the project's full uniqueness can be properly appreciated. From the living room of an apartment with a floor-to-ceiling window, you look south onto the tops of trees up to nine meters high that are in planters 1.3 meters deep on the balcony below. Looking to the north through shrubbery, tree trunks and branches, there is the silhouette of the snow-covered Alps in the distance.

It is one of those rare sunny November days in one of Europe's most densely populated large cities where air pollution is so rampant that the authorities are forbidding driving and closing schools.

The equivalent of 2.5 acres of green

The Bosco Verticale could be described as an attempt to bring the forestland Milan so urgently needs back to the built-up city. The 20,000 shrubs and 800 trees on the balconies, covering a total surface of 8,900 square meters, incidentally serve aesthetic purposes, but they are primarily meant to ensure a better micro-climate in the apartments, filtering dust particles from the air and producing oxygen.

As natural green insulation material, the balcony gardens also protect against heat, cold and noise, and help save energy. The architectural landscaping concept was developed by agronomist Laura Gatti working together with the University of Milan and scientists at Karlsruhe's Institute of Technology.

It was a real fight to convince the building owners, American project developers Hines, of their plant concept, Gatti says as she leads visitors through two unoccupied apartments.

The developers simply couldn't believe that the oaks, hazelnut trees, beechwoods, plum trees and Persian ironwood trees could withstand local winds of up to 160 kilometers an hour. The trees had been prepped for two years at a tree nursery for their future life in the highrise.

"We were pretty sure that anchoring the trees in the 1.3-meter-deep balcony planters and concrete ceilings was enough, but the developers wanted to make absolutely sure and stuck the entire plant package into a wind canal in Miami and subjected it to winds at speeds of up to 190 kilometers an hour," Gatti says. "That was how we got the final proof that our calculations were correct."

But the residents, whose apartments cost between one and 10 million euros each, won't be out there with clippers, shovels and watering cans. The plants are watered automatically with the help of an electronically controlled system that pumps non-potable water from the ground water via hoses into the balcony planters.

A permanently installed crane on the roof makes controlling the growth of the trees possible. Three gardeners have been hired to maintain the vertical woods that cover the equivalent of one hectare (2.5 acres). They are charged with pruning, fertilizing, and generally caring for the plants year-round.

For reasons of aesthetics and safety, residents are not allowed to make individual additions to the plantings, so rose breeders will have to find somewhere else to pursue their hobby. "But most of the residents will be thankful that plant maintenance is taken off their hands," Gatti says.

Of course, that luxury has it price. Residents have to pay some seven euros per square meter of living space annually for the care of their woods.

Standing in the huge, minimally furnished entrance area of the larger tower, Boeri, the architect, thinks it's a pity that so few can afford to live in Bosco Verticale.

But the buildings are also a prototype, he says, and to develop prototypes more money is always required in the beginning. The costs would pay for themselves if the model is replicated. Thanks to the international prize, the chances of that happening are quite good.

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Iran-Saudi Arabia Rivalry May Be Set To Ease, Or Get Much Worse

The Saudis may be awaiting the outcome of Iran's nuclear talks with the West, to see whether Tehran will moderate its regional policies, or lash out like never before.

Military parade in Tehran, Iran, on Oct. 3


LONDON — The Iranian Foreign Ministry spokesman Saeed Khatibzadeh said earlier this month that Iranian and Saudi negotiators had so far had four rounds of "continuous" talks, though both sides had agreed to keep them private. The talks are to ease fraught relations between Iran's radical Shia regime and the Saudi kingdom, a key Western ally in the Middle East.

Iran's Foreign Minister Hossein Amirabdollahian has said that the talks were going in the right direction, while an Iranian trade official was recently hopeful these might even allow trade opportunities for Iranian businessmen in Saudi Arabia. As the broadcaster France 24 observed separately, it will take more than positive signals to heal a five-year-rift and decades of mutual suspicions.

Agence France-Presse news agency, meanwhile, has cited an unnamed French diplomat as saying that Saudi Arabia wants to end its costly discord with Tehran. The sides may already have agreed to reopen consular offices. For Saudi Arabia, the costs include its war on Iran-backed Houthis rebels fighting an UN-recognized government in next-door Yemen.

The role of the nuclear pact

Bilateral relations were severed in January 2016, after regime militiamen stormed the Saudi embassy in Tehran. Amirabdollahian was then the deputy foreign minister for Arab affairs. In 2019, he told the website Iranian Diplomacy that Saudi Arabia had taken measures vis-a-vis Iran's nuclear pact with the world powers.

It's unlikely Ali Khamenei will tolerate the Saudi kingdom's rising power in the region.

He said "the Saudis' insane conduct toward [the pact] led them to conclude that they must prevent [its implementation] in a peaceful environment ... I think the Saudis are quite deluded, and their delusion consists in thinking that Trump is an opportunity for them to place themselves on the path of conflict with the Islamic Republic while relying on Trump." He meant the administration led by the U.S. President Donald J.Trump, which was hostile to Iran's regime. This, he said, "is not how we view Saudi Arabia. I think Yemen should have been a big lesson for the Saudis."

The minister was effectively admitting the Houthis were the Islamic Republic's tool for getting back at Saudi Arabia.

Yet in the past two years, both sides have taken steps to improve relations, without firm results as yet. Nor is the situation likely to change this time.

Photo of Iranian Supreme Leader Ali Khamenei in 2020

Iranian Supreme Leader Ali Khamenei in 2020

Riyadh's warming relations with Israel

Iran's former ambassador in Lebanon, Ahmad Dastmalchian, told the ILNA news agency in Tehran that Saudi Arabia is doing Israel's bidding in the region, and has "entrusted its national security, and life and death to Tel Aviv." Riyadh, he said, had been financing a good many "security and political projects in the region," or acting as a "logistical supplier."

The United States, said Dastmalchian, has "in turn tried to provide intelligence and security backing, while Israel has simply followed its own interests in all this."

Furthermore, it seems unlikely Iran's Supreme Leader Ali Khamenei will tolerate, even in this weak period of his leadership, the kingdom's rising power in the region and beyond, and especially its financial clout. He is usually disparaging when he speaks of Riyadh's princely rulers. In 2017, he compared them to "dairy cows," saying, "the idiots think that by giving money and aid, they can attract the goodwill of Islam's enemies."

Iranian regime officials are hopeful of moving toward better diplomatic ties and a reopening of embassies. Yet the balance of power between the sides began to change in Riyadh's favor years ago. For the kingdom's power has shifted from relying mostly on arms, to economic and political clout. The countries might have had peaceful relations before in considerably quieter, and more equitable, conditions than today's acute clash of interests.

If nuclear talks break down, Iran's regime may become more aggressive.

Beyond this, the Abraham Accord or reconciliation of Arab states and Israel has been possible thanks to the green light that the Saudis gave their regional partners, and it is a considerable political and ideological defeat for the Islamic Republic.

Assuming all Houthis follow Tehran's instructions — and they may not — improved ties may curb attacks on Saudi interests and aid its economy. Tehran will also benefit from no longer having to support them. Unlike Iran's regime, the Saudis are not pressed for cash or resources and could even offer the Houthis a better deal. Presently, they may consider it more convenient to keep the softer approach toward Tehran.

For if nuclear talks with the West break down, Iran's regime may become more aggressive, and as experience has shown, tensions often prompt a renewal of missile or drone attacks on the Saudis, on tankers and on foreign shipping. Riyadh must have a way of keeping the Tehran regime quiet, in a distinctly unquiet time.

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