An Urban Farm in Paris

In France, one inhabitant in three dreams of owning their own vegetable garden. For those living in the cities, this remains a dream. The lack of open spaces, which could be dedicated to such activities is the main reason. But things could easily be turned around: Paris, the capital, has 314 hectares of flat roofs and warmer temperatures than anywhere in the Ile-de-France region. In other words, Paris could potentially become a suspended vegetable garden. Some people here are actively initiating this change. “Nobody had thought of this because Parisian buildings are perceived as an untouchable heritage. But this can change; people see what is happening in other big cities around the world,” explains Fabienne Giboudeaux, deputy mayor in charge of green spaces and biodiversity. Mrs Giboudeaux has launched a call for proposals in order to create 15 farms in the heart of Paris before 2020. The challenge is threefold: to reduce the costs of heating or cooling with green roofs, to recycle organic waste and, last but not least, to develop short distribution channels between producers and consumers.

The big names in French cuisine were the first to respond to this initiative. They saw in it a challenge and a chance to have access to products of better quality. Tomatoes are a good example: if today they have lost all their taste, it is because they have been modified to survive the vagaries of transport. Cultivating fruits and vegetables in situ automatically means returning to superior produce.

In the meantime, green initiatives are popping up frequently. This includes projects undertaken by UrbAgri, which is currently building on roofs at Seine-Saint-Denis and the Val-de-Marne, or the ‘ready-to-use’ roof gardens realised by Mauvaises Herbes. 

There are a growing number of business opportunities since everyone in the city wants a garden, but people just don’t know how to start. 

The landscaper and co-founder of BacSac, Virgil Desurmont, has found a way to offer practical solutions. The young company sells gardening bags that are easy to disseminate on roofs, balconies, sidewalks or even on very small spaces. Such a simple idea is today a great marketing success. Playful, easy, sustainable and ultra-satisfying, gardening and producing one’s own vegetables has became the trend recently and has now conquered cities.

In architecture, the ambitious gardening farm project in Paris, designed by Clément Baehr and his team, illustrates this trend. The project of rue Castagnary in the 15th arrondissement of the capital combines the urban challenges with the social aspect of this gardening fever. It is both a programmatic reflection and an ‘idea’ project on an urban scale.

The plot of rue Castagnary is a narrow piece of land running along the railway tracks of the SNCF(France’s national state-owned railway company). It is about 150 metres in length and the width varies from six metres to 20 metres. Currently, warehouses are built on the whole plot. The plot of rue Castagnary, backed by this urban barrier of the SNCF tracks benefits from an exceptional location as a connecting site between the different zones of activities and life.

On a larger scale, rue Castagnary is an important artery that leads from the Boulevard des Maréchaux to the heart of Paris. This entry into the city can be emphasised by offering a continuous setting of activities all along it, from the Porte de Vanves up to the Rue de la Convention. Besides, before the SNCF built its warehouses on the site, a fish market used to be a well-sized place of exchange frequented by local residents. 

The architect and landscape team naturally envisaged the idea of giving a meeting place back to the people. They set up a large greenhouse dedicated to vegetable production.

As etablished by deputy mayor Giboudeaux, the main goal of the urban farm is to reduce the distribution channels of products by growing food locally and making use of local waste. Alongside that, the project offers a location for agricultural holdings in urban areas, provides green roofs with spaces shared by the inhabitants that motivates social cohesion and finally assists in the education of young people about vegetable gardening. Urban planning, economy, sociability, sustainability and health are brought together in one singular building.

The urban farm of Baehr’s team has three elements. The focal point of the project, the landmark, is the glasshouse. It is also the highest part of the building, so placed as to capture as much light as possible. The glasshouse is southward oriented and the inclination of its facade allows direct light to penetrate several metres deeper into the building. The organization of the vegetable production in the glasshouse is also arranged according to the sunlight: from the tomato that needs a lot of light to the mushroom that requires much more shade. The next essential element of the building is the sculptural protection wall. Since night lighting will be installed to increase productivity, nearby housing needs to be protected from this artificial luminosity. The glasshouse extension houses a covered market. This vegetable market is organised along a plant wall protecting residents from the noise of the tracks.

The next step of the architecture design process was to incorporate these three simple elements in order to extend the public space into the vegetable market and at the same time to guide visitors from the hall through the market. Finally, some holes were added to the massing to bring light into the market and to create several accesses from the common spaces up to the roof gardens.

The elongated shape of the plot allows the designers to create a building that accompanies the pedestrians into the vegetable market for more than 100 metres if they wish. The walk throught the market is punctuated by access to the roof gardens. Visitors circulate around these copper-coloured elements to exit or enter the market. The market interior space is literally a physical extention of the public domain. The accesses to the roof gardens are deliberately set back from the alignment of the public road: this emphasises the effect of floating green covers above the street and, at the same time, allows outside and inside spaces to merge into each other. This aligns with the initial idea of the architects to create a (interior and exterior) place where sharing and meeting one another is the main goal.

The functional principle of the project is very simple, inspired by the basic ideas of the permaculture. Permaculture is a movement created in the ’60s and ’70s in North America; a way of living, working, producing food with a minimum footprint on earth. In other words, everything has multiple uses and purposes. Waste does not exist. At the Parisian farm, vegetable production in containers is carried out in the glasshouse. This production is sold on site in the vegetable market, also transformed if necessary on site and the organic waste from the production and the market is used to feed future productions of the glasshouse.

With the same spirit, thought has gone into the water cycle. Because of the dimensions of the plot, rainwater recovery is very important. This water is stored in a pool placed at the foot of the glasshouse and fulfils all the water needs of the building (domestic hot water, cleaning of the market, external watering).

The project at rue Castagnary shows that on every piece of ground in the city, even on a site that, at first glance, does not seem very appealing, a lot can be done.