In cities, soil is often seen as subsoil. A technical layer on which we build, plan and design. But what happens when we approach soil not as a passive foundation, but as a living system with which people are constantly in relationship?

That question is at the heart of Rooted in Soil. In this interview, Laura Thomas (TU Delft) and Catherine Vroon (Erasmus University Rotterdam) explain how the relationship between people and soil takes shape in collective food gardens. Not only through soil measurements or design principles, but also through volunteer work, compost, water, plants, social encounters and the everyday act of working with your hands in the earth.

The project received support from the Resilient Delta initiative and the LDE Climate & Biodiversity programme. That combination made it possible to expand the team, study several places and approach the subject from different perspectives.

A different form of soil knowledge

According to Laura, the research starts from a broader observation: in many urban contexts, people have become disconnected from their natural environment. Soil knowledge is often approached technically, through diagrams, measurements and categories. That knowledge is important, but it does not tell the whole story.

Rooted in Soil therefore also looks at other forms of knowledge. Knowledge that emerges by doing, trying, observing and repeatedly responding to what a place asks for. In food gardens, this happens every day. Volunteers, gardeners and involved residents work not only on the soil, but with the soil.

Catherine describes the research as an exploration of how the relationship between people and soil takes shape in food gardens. It is not only about ecology, but also about social connection, care, food production and access to green space.

Especially in cities, places where people come into direct contact with soil are scarce. Food gardens do offer that possibility. They are often accessible, collectively organised and connected to broader urban issues such as biodiversity, food security, health and social resilience.

What is a social soil?

An important concept in the research is the “social soil”. By this, the researchers do not only mean that people meet each other in a garden. It refers to a broader way of looking: soil is partly shaped by human action, and that action is in turn influenced by the soil.

Making compost, watering, removing weeds, choosing plants, making harvest plans and guiding volunteers are all actions that influence soil formation. At the same time, every soil asks something different in return. A sandy soil responds differently from a compact clay soil. A plant that grows well in one place may do less well somewhere else. In this way, an ongoing dialogue emerges between people, plants, soil and place.

That idea also returns in the “soil characters” developed within the research. These are not separate objects, but ways of making visible which elements play a role in the relationship between people and soil. Think of compost, water, plants and volunteers, but also of a canteen. A canteen may not seem like a soil character, but it can bring people to the garden. Because they gather, work and care there together, care for the soil also emerges.

In this way, Rooted in Soil shows that social and ecological resilience are not separate from each other. People sometimes come to a garden mainly for its social aspect. But precisely because they do something together there, they contribute to the natural system.

Research with hands in the earth

The approach of Rooted in Soil combines visual ethnography and spatial design. Catherine brings expertise in film, observation and participatory research. Laura, Marie Benninghoven and Nafsika Efklidou work from design, drawing, ordering and spatial thinking.

In practice, this means that the team does not only conduct interviews or observe from a distance. They work alongside people in the gardens, film, draw, order and repeatedly bring their insights back to the people who work there. The soil characters, for example, were developed on the basis of conversations and fieldwork, and are then discussed again with the people involved in the gardens.

This makes the research co-creative. The gardens are not only research objects, but places where knowledge is created together. The team describes the process as a continuous feedback loop: observing, taking part, visualising, bringing back, adjusting and looking again.

For Catherine, this is an essential part of visual and participatory ethnography. By taking part yourself, a form of experiential knowledge emerges that is less easily revealed in an interview or policy document. On the design side, the work is carried by Laura Thomas, Marie Benninghoven and Nafsika Efklidou. Together they draw, order and visualise the insights from the field, and explore how design can help make the relationships between people and soil visible. Laura says that this combination of design and ethnographic work has also changed the way she looks as a designer. While design often works towards one strong concept, ethnographic work requires you to keep questioning your own assumptions.

The local soil speaks back

One of the key insights from the first phase is that the local soil “speaks back”. That may sound obvious, but the researchers emphasise that policy and design often still do not take this sufficiently into account.

Spatial planning often works with general principles. These can be valuable, but they only gain meaning when they are applied in a specific soil, in a specific place. In the food gardens studied, people often work from similar permaculture principles, in which care for the natural system and balance are central. Yet the practice works out differently in each place.

One soil asks for different plants, different forms of nourishment or a different rhythm of work than another. Through trial and error, gardeners learn what a place needs. According to Laura and Catherine, that bottom-up perspective is valuable for designers, policymakers and municipalities.

The research therefore does not argue for a simple recipe. Instead, it shows that designing with soil requires attention, time and responsiveness. It is not only about deciding beforehand what needs to happen, but about continuing to look at what the soil does after a design principle has been applied.

Resilience is also relational

For cities such as Rotterdam, the practical connections are clear. More open soil can contribute to water infiltration, biodiversity and cooling. Food gardens can also contribute to urban food production, access to nature and social connection.

But Rooted in Soil wants to go further than asking what soil can solve for the city. Laura and Catherine want to prevent soil from being seen once again only as an instrument. Soil is not a solution we can deploy without also taking responsibility ourselves. Care for the soil and the care the soil gives back must remain in balance.

This is also where the link with resilient cities and deltas lies. Resilience is not only about technical measures or ecological processes. It is also about relationships: between people, between people and places, and between social and natural systems.

In the gardens, it becomes visible how these relationships can work. People find structure, contact and meaning there. Some stories show that working in the garden helps people get out of their heads and do something with their hands again. At the same time, their presence contributes to care for the soil. Social conditions make ecological care possible, and vice versa.

Collaboration between RDi and LDE

The support from RDi and LDE primarily created space. Through the combination of funding, the team was able to study several locations and approach the subject from different angles. This created a broader and more balanced picture.

The collaboration also brought plurality in terms of content. In one context, the emphasis was more strongly on the position of the people in the garden and the social meaning of the work. In another context, ecology, creativity and imagination came more explicitly to the fore. These different angles fit a project that is precisely trying to understand soil not from one discipline alone.

In this way, Rooted in Soil aligns with the mission of the Resilient Delta initiative, in which social, ecological and spatial issues come together. At the same time, it fits the focus of LDE Climate & Biodiversity on the relationship between climate, biodiversity and social change.

A documentary as part of the research

In addition to the report, the team is working on a documentary. The film is not only intended to make the research results more accessible to a wider audience. The documentary is also part of the research process itself.

Images can show what is harder to convey in a report: the atmosphere in a garden, the care with which people plant a tree together, the jokes in between, the way people move, look and collaborate. The design process is also shown, from developing the soil characters to drawing, ordering and bringing them back to the people in the gardens.

The film can also become meaningful for the gardens themselves. For places under pressure from urban development, the documentary can show what is lost when a garden disappears. Not only land or greenery, but also community, knowledge, care and a relationship with the soil that has been built over time.

The screenings are expected to be organised in the autumn. In this way, Rooted in Soil will continue beyond the academic context, towards residents, gardens, designers, policymakers and other people involved.

Learning to listen to the soil

Rooted in Soil shows that soil is more than a technical subsurface. Soil is alive, dynamic and interwoven with social practices. Anyone working on climate adaptation, biodiversity or urban development therefore cannot only speak about soil from the drawing board.

The core of the research is not that soil will solve our problems. It is rather an invitation to understand our relationship with soil anew. With attention to local knowledge, to what a place gives back, and to the people who learn every day by working with their hands in the earth.

Because anyone who looks closely at food gardens sees that resilience does not emerge from one measure or one design principle. It emerges in the interaction between people, soil, plants, water, care and time. That is where the lesson of Rooted in Soil begins: the soil is not a silent underground. The soil speaks back.

Thomas, L., Benninghoven, M., Efklidou, N., & Vroon, C. (2026). Rooted in Soil: Onderzoeksrapport fase 1. Delft University of Technology, Faculteit Bouwkunde.

Photo and image: Thomas et al. (2026).