The 90/91 route becomes green with Milano Green Circle
Milano Green Circle 90/91 is a project of the City of Milan in collaboration with Armani Group. The overall project goal is to plant 350 new trees and over 60,000 shrubs and perennial herbaceous on the 90/91 trolleybus route. Work began in autumn 2024 along the first section, stretching from Piazzale Brescia to Piazza Bolivar. The project supports the ecological transition and the integration of nature into urban spaces. Just as roads and highways only function when connected, urban greenery should not be fragmented into small, isolated pockets. In fact, when green infrastructure forms a continuous network, its benefits multiply—making the city more livable and sustainable.
Ecosystem services
Milano Green Circle 90/91 aims to integrate the following benefits, technically known as ecosystem services, which are essential for both environmental and social well-being:
Stormwater
Management and Optimization
Creating shallow depressions in the soil to collect and channel rainwater toward the areas where the plants will be placed, in order to optimize irrigation.
Particulate Matter
Reduction and Control
Thanks to hedges made of both evergreen and deciduous plants, fine particulate matter will be captured throughout the year, helping to reduce urban pollution.
Biodiversity
Conservation and Enhancement
Planning bloom cycles so that flowering occurs throughout all seasons, ensuring and preserving the biodiversity of these microsystems.
Soil
Regeneration and Protection
Use of herbaceous plants that enrich the soil with nitrogen and/or have dense root systems to improve its fertility and structure.
Noise Pollution
Containment and Reduction
Sound is distorted and deflected by the presence of vegetation, which alters how it is perceived.
Project progress
In 2025, the interventions carried out by Cooperativa Il Giardinone focused on the stretch between Piazzale Brescia and Piazza Bolivar, specifically along Viale Bezzi, Viale Misurata, and Via Ranzoni. More than 4,300 shrubs and 1,300 perennial herbaceous plants were planted along over 1,730 linear meters of the ring road.
The interventions were designed to respond to the specific characteristics of the area, such as the slope of the land and the presence of the Olona River flowing beneath the site, with the aim of promoting rainwater infiltration and reducing water consumption for irrigation.
In autumn 2026, the Milano Green Circle 90/91 will continue to grow along the stretches of Viale Sondrio and Viale Tonale, considered among the most complex areas from both a climatic and morphological perspective. Here, particularly resilient species adapted to high temperatures and water scarcity will be introduced, including wall germander, Jerusalem sage, Abelia × grandiflora, curry plant, Montpellier maple, and hawthorn. The new plantings will also be integrated among the existing trees, avoiding interference with root systems while preserving the functionality of the roadway and dedicated transit lanes.
During the initial phase of the project, efforts were focused on preserving existing shrubs by redesigning their management model. Damaged plants were removed and replaced with new species, including bare-root white rose, rowan, quince, and cydonia, while maintaining a two-layer planting design: one featuring evergreen shrub hedges, and the other varying depending on the available space.
The effects on urban wildlife are already measurable: around 110 insects species have been recorded in areas managed with reduced mowing practices. In green areas, the number of daytime butterfly species has increased by 58%. House martins and goldfinches are also returning to nest within the city’s ecological corridors.
Respecting nature’s timing is essential to ensuring the full development of this project. As the newly planted species are still in their early stages, they will follow their natural growth cycle with the aim of integrating harmoniously into the avenues where they have been introduced. By the end of the project’s three-year timeline, the greenery will gain greater density and a more lush appearance, with visible benefits for the urban environment that will continue to strengthen over the long term.
The Milan Design Week activation
To raise awareness about the Milano Green Circle 90/91 project, an electric Ape Car by Emporio Armani was distributing exclusive tote bags to passersby at Via Manzoni 31, right in front of the Armani Store. Each bag contained a plant pot and plantable postcards—a unique experience blending sustainable design and nature.
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