The benefits of green, nature-rich urban centres are well-known: they help cities become more resilient to climate change by offering natural protections from weather phenomena like extreme heat and flooding, while also providing residents with more attractive public spaces where they can reconnect with nature and each other. But weaving this green space into densely built city centres, where space is limited and competing pressures are high, is a challenge.
GreenDense aims to tackle this challenge by supporting six cities across five countries in North-West Europe pilot small-scale green infrastructure, creating a connected ‘mosaic’ of green within their urban centres. To help them on this journey, three knowledge partners are working alongside the pilot cities, guiding them through every stage of the process.
One such partner is Plante & Cité, a French non-profit dedicated to research, experimentation, and innovation for greener cities. We spoke to Plant and Cité’s Alice Meyer about the organisation’s role in supporting the GreenDense project, what she sees as the biggest challenges in implementing more greenery into dense urban centres and what gives her hope that greener, healthier European cities are in reach.
Can you briefly introduce Plante & Cité and your role as a knowledge partner on GreenDense?
Sure! Plante & Cité is a non-profit and the French technical center dedicated to studies, research and experiments on green spaces and nature within cities. Our actions cover multiple domains from agronomy of urban soils to ecological maintenance and greening strategies through nature-based solutions. We have long-standing experience helping local governments implement green infrastructure that supports biodiversity, public health and climate adaptation.
As a knowledge partner on GreenDense, we support partner cities in the design, implementation and activation of their pilot and mosaic sites, sharing scientific and technical expertise across a range of environmental topics.
How have you supported the pilot cities so far, and why is this work so important?
We’ve focused especially on developing innovative models for the long-term maintenance of the pilot sites. One key output is a Manual for the Long-Term Sustainability and Maintenance of Mosaic Green-Infrastructure (GI), designed as both a communication tool and an educational resource to help cities promote ecological maintenance and foster long-term public participation.
We also provide guidance on practical issues such as soil de-sealing, cohabitation between roots and underground networks, and greening in cultural heritage sites. GreenDense is a valuable opportunity to test ecological maintenance practices in small-scale greening initiatives while building durable public involvement - a crucial challenge for cities.
What do you see as the biggest obstacles to integrating more green space into dense urban environments?
One of the biggest challenges is getting local communities engaged in the long run. In dense urban areas, limited space and competing priorities can make greening efforts difficult to maintain without strong, lasting public involvement.
GreenDense responds to these challenges by promoting a mosaic of small-scale green interventions that optimise limited space and strengthen ecological connectivity. These areas provide multiple benefits (cooling, biodiversity, social cohesion, water management) and are developed through co-design and public participation to ensure they truly meet local needs. This bottom-up approach helps create green spaces that communities feel joint ownership of.
Is there a challenge related to “urban greying” that deserves more attention?
Impermeable sealing of soils is a major yet often overlooked issue. It degrades soil functions, disrupts the water cycle, reduces biodiversity and carbon sequestration, and contributes to both flooding and urban heat stress. But sealed soils are not dead - they’re in a kind of coma. Desealing, even at a small scale like removing a few cobblestones, can slowly restore ecological functions and have a real impact.
What gives you hope that greener, healthier cities are in reach?
What gives us hope is seeing increasing public awareness of the benefits of urban greening, even at small scales, as well as growing interest in ecological maintenance that respects natural cycles.
Within the GreenDense project itself, we’ve already seen a lot of progress that also helps feed that sense of hope. For example, seeing pilot cities successfully bring communities together to co-create greener neighbourhoods. This community aspect is vital, especially because implementing new urban green spaces doesn’t only carry environmental benefits, they can also act as vehicles for social cohesion and environmental learning.
The transnational collaboration element of GreenDense also helps show the value, and importance, of cross-European collaboration to help build greener, healthier cities. Sharing experiences and expertise allows cities to build knowledge that lasts beyond any one project.
We will have many more ‘this is why we do this’ moments as the pilot sites get implemented and activated - and we can’t wait to see the impact they will go on to have!