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From the Field

Flowers under the flagstones

Cédric Ansart and Emmanuel Boutefeu explore new ways of enhancing city streets through the small-scale greening of footpaths and façades, and show how “asphalt flowers” can help to transform the way we share these spaces and blur the lines between the public and private domains.

Series : Nature in the City

In recent years, flowers and climbing plants have been burgeoning along the footpaths and façades of city streets. This “greening” of urban thoroughfares is the result of operations implemented at the initiative of residents, local activist groups, artists and sculptors (Coloco 2012), or even neighbourhood councils seeking to encourage self-managed gardening in order to raise awareness of the role played by plants in the city. These street-gardening schemes go by different names in different parts of France – “floral micro-plantations” in Lyon, “linear gardens” in Lille, “Beautify Our Walls” in Rennes or “Green Your Façades” in Strasbourg, for example. But they have one thing in common : these small green spaces are radically modifying the appearance of urban streets and are having unexpected impacts. Whenever footpaths are bordered by front gardens, open courtyards or green areas set back from the road (where frontages have been realigned), the result is a profound change in the atmosphere, scale and uses of the street – and in the practices of municipal parks and gardens employees.

Plants liven up footpaths in Lyon (cc) Emmanuel Boutefeu

A green revolution in municipal practices

Today, a number of local councils are exploring new ways of designing and maintaining public spaces. The aim of these operations is to provide a relevant response to technical constraints and recurrent criticisms about the lack of innovation when it comes to urban public spaces : on the one hand, there is a feeling that parks and gardens have become too standardised and sanitised ; on the other, issues relating to the environment, well-being and health are challenging traditional maintenance methods. Simply weeding city footpaths is increasingly proving a headache (Menozzi et al., 2011). The slightest crack at the foot of a building or fissure in the asphalt opens the door to opportunistic plants, undesirable species and wild flowers. Indeed, over 240 plant species are capable of colonising the streets, tree bases, roofs, walls and wastelands of the towns, cities and villages of France (Machon 2012). The city is an ideal home for this spontaneous flora, which also benefits from our means of transport to spread their seeds.

For many, these weeds reflect a clear failure in terms of maintenance, for which chemical weed control is no longer a sustainable solution. Since the mid-2000s, the growing success of differentiated management schemes for green spaces, combined with environmental management systems (ISO 14001 certification, for instance), and the rise of associations seeking to protect their living environment (following measures such as the Grenelle Environment Round Table and the 2018 Écophyto Plan) have led to changes in local authorities’ weeding strategies. Accordingly, cities such as Rennes, Lyon, Lille, Paris and Versailles have decided to experiment with the idea of planting flowers along the edges of footpaths and façades. “Planting rather than weeding” and “replacing unwanted weeds by chosen plants” are the new philosophies in place for highways officials.

The aim is to establish perennial vegetation instead of paved surfaces in order to reduce the spread of pollutants at source and reduce costly and time-consuming human intervention such as pulling out weeds by hand, hoeing and flame weeding. Many cities have implemented a “zero chemicals” approach to managing their green spaces, although certain specific treatments are still used in municipal greenhouses. The comments of Cathy Biass-Morin (2011), director of the parks and gardens department at Versailles city council, sums up this new doctrine perfectly :

“As soon as we see a clump of weeds at the foot of a wall, instead of removing it, we decide to vegetate the entire street frontage in order to achieve a landscaping effect and a high quality of floral displays along the street throughout the year. The end result is that we intervene in a given street no more than three times a year – once or twice to remove faded flowers and once to weed by hand.”

Other council departments have adopted an educational approach to promoting biodiversity, by encouraging residents to take action themselves to create and manage natural spaces – whether flower gardens, vegetable gardens, meadows or wilderness areas – in their street or neighbourhood.

From activism to community planting

“Greening footpaths to more effectively integrate grasses and weeds into the streetscape, making them desired rather than undesirable plants” – this is the philosophy behind certain residents’ groups working towards the self-managed blooming of their neighbourhoods. In Lyon and Villeurbanne (the two cities at the heart of the Greater Lyon urban area), a number of streets have been micro-planted with flowers. In 2006, an operation called “Les Petits Brins Zurbains” – loosely based on the community gardens movement in New York (Reynolds 2010) – was initiated by the association Brin d’Guill’ in the Guillotière neighbourhood of Lyon. Various reasons are given for this form of green activism : “we plant in order to reclaim the city, to promote interaction between residents, to eat what we produce, or simply out of idealism”. On the advice of Bernard Maret, from Lyon city council’s parks and gardens division, a first experiment took place in the neighbourhoods of Saint‑Just, Montchat and La Guillotière. [1] In small trenches 12 cm (4.7”) long and 3 cm (1.2”) wide, dug out of the pavement [2] with an angle grinder, residents can easily insert small pots of plants, creating a “botanical identity” for the street. Since then, these pioneering exercises have become case studies. Today, Lyon city council makes similar trenches – cut into the macadam along street frontages, at the base of fences and in derelict sections of street – available to resident volunteers, after first checking that the quality of the substrate and the configuration of underground utility lines are compatible with the root systems of these “asphalt flowers”. In addition, the city council delivers advice and provides lists of plants according to the soil type, the orientation of the footpath (in terms of exposure to sun and shade) and the nature of the plant at maturity (climbing, aromatic, perennial, annual, groundcover, etc.). It is then up to each resident to buy plants, exchange cuttings and organise watering and maintenance.

Micro-plantation of flowers in the Guillotière neighbourhood of Lyon (cc) Cédric Ansart

In Rennes, the “Jardinons nos rues” (“Garden Our Streets”) initiative also allows inhabitants to brighten up their neighbourhood by greening façades, footpaths, and the bases of trees. Since 1999, around 50 such projects have been completed, to the delight of residents and passers-by alike. Given the success of this initiative and the growing number of requests from inhabitants, the city council has invited volunteer gardeners to sign a street-garden management agreement with regard to the “greening of municipal thoroughfares”. This is accompanied by some basic rules :

  • a clear passage of at least 1.40 m (4’7”) must be maintained on all footways ;
  • weedkillers and other chemicals must not be used ;
  • fertilisers cannot be used and thorny plants must not be planted ;
  • planting at the foot of poles and street furniture is prohibited ;
  • climbing plants must not be planted at the base of trees ;
  • plants must be watered and pruned regularly, and dead leaves and green waste removed to ensure the footpath remains clean and tidy at all times.
Residents maintain footpath gardens themselves (cc) Cédric Ansart

Developing green spaces in this way allows residents to appropriate neighbourhood spaces, by gardening (literally) on their doorstep and taking responsibility for planting around trees growing close to their homes. By making the public domain – the street – a private community space, street gardens call for new forms of thinking and experimentation. This kind of participatory action restores local residents’ ability to undertake collective action, while also creating social ties among neighbours, and changing our view of the weeds that grow in the cracks in the pavement. “Asphalt flowers” can be something of a challenge for councils’ sanitation and highways departments, requiring them to resolve their differences and coordinate their action regarding the best use of the street, reconciling considerations such as cleanliness, how best to integrate plants into the urban fabric in sites designed to drain off water, or the proportion of street space to be dedicated to pedestrians and cyclists compared to other (motorised) modes of transport. Indeed, as we have seen, small-scale street planting changes the way footpath space is shared, and in particular shifts the line between public and private spaces, creating unexpected ambiences and amenities. All of which underlines the extent to which a seemingly simple measure such as street gardens can in fact be a surprisingly complex issue with many ramifications.


  • Biass-Morin, C. 2011. “L’expérience versaillaise zéro phyto dans les cimetières”, Les Rencontres de Natureparif, 23 March.
  • Cachin, S. 2010. Je jardine ma ville. Échange avec Sylvie Ligny, Paris : Rue de l’Échiquier.
  • Coloco. 2012. Fertiles Mobiles, Paris : Tout Contre éditions.
  • Machon, N. 2012. Sauvages de ma rue : guide des plantes sauvages des villes de France, Paris : Muséum national d’histoire naturelle (MNHN) and Le Passage.
  • Menozzi, M.-J., Marco, A. and Léonard, S. 2011. Les Plantes spontanées en ville. Écologie et sociologie, literature review of the Acceptaflore study, Angers : Plante & Cité.
  • Reynolds, R. 2010. La Guérilla jardinière, Gap : Éditions Yves Michel.

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En savoir plus

  • Butor, M. and Delhoume, O. 2010. Jardins de rue au Japon, Geneva : Éditions Notari.
  • Soulier, N. 2012. Reconquérir les rues. Exemples à travers le monde et pistes d’actions, Paris : Éditions Ulmer.

Pour citer cet article :

Cédric Ansart & Emmanuel Boutefeu & traduit par Oliver Waine, “Flowers under the flagstones”, Métropolitiques, 8 octobre 2014. URL :

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