In the 21st century, we have become used to cities dominated by brown and grey shades of stone and concrete, with vegetation restricted to purpose-built areas – tree pits, flower beds or containers. Vegetation growing outside of these areas is usually associated with the word “weeds” and removed, using chemical or mechanical methods.
Let’s go back in time. In agricultural environments, undesired plants became a problem as soon as mankind started to domesticate wild plants (10,000 BC). With movements of populations, plants spread around the globe, becoming problems in some areas, opportunities in other countries. The development of large-scale agriculture during Roman times, and then during the Middle Ages was accompanied by the development of weeding machinery, helping to reduce the number of weeds (but sometimes encouraging their growth too – some plant species prefer disturbed ground).
But what about our cities? Were the streets of our cities in the past green and wild, or mineral and well-weeded?
In Tudor gardens, weeding was done manually, often by poor women working for very low wages, bending all-day long to remove unwanted plants between desirable flowers. In The Riverside Gardens of Thomas More’s London, the historian Paul Christianson gives accounts of large numbers of “weeding women”, working in the gardens of York Place and Hampton Court in the 16th century. Paradoxically, it was also at that time that our knowledge of the wild flora increased, with the rediscovery of many ancient Roman or Greek books on natural history. The medicinal properties of some weeds were recognised, and they were used in remedies.
The streets of many cities were filled with wild plants. This is still acknowledged today through some street names. In Paris, for example, there are several “Nettle Streets”, legacies of a time where they would populate the bare ground. Of course, labour-intensive, manual weed removal methods, were commonly used in cities, as illustrated in this 1882 painting, where women in the Dutch town of Hoorn are brushing and raking a quay.
In the 19th century, particularly with the expansion of cities and paved streets, people started to look at other methods that could reduce the amount of manual weeding needed, such as chemicals. In a French journal on household chores published in 1831, I found this recipe for a “method to kill grass that grows in garden alleys and between cobblestones in courtyards“: boil water in an iron cauldron, and add, per 60 liters, 12 pounds of lime and 2 or 3 pounds of sulfur. This will “purge the soil of rebel herbs for several years“. This method is in fact quoted in several English publications, as a way to clear the “very injurious as well as unsightly” plant growth between the stones of pavements.
Nowadays, any weeds removed are likely to be binned or composted. But in the 19th century, these weeds also had an economic value. In the social study London Labour and the London Poor, published in the 1840s, the Victorian journalist Henry Mayhew describes “chickweed and grunsell” sellers, who would gather bunches of nettles, chickweed, plantain, dandelion or groundsel from rich people’s gardens, agricultural fields or parks. They would sell these in the streets as fodder for caged birds, which had become particularly popular in the Victorian times (“canaries, goldfinches or linnets”).
Interestingly, not everyone considered pavement plants as something to be destroyed. For botanists, they were a welcome curiosity. In 1884, a French botanist published a catalogue of plants growing on pavements and quays in Paris. This was one of the first accounts of “urban biodiversity“. He lamented about the loss of many plants to urbanisation, but pointed out that some of these plants seemed to survive in the grids of the newly planted street trees. Early signs of “green infrastructure”?
More generally, weeds were seen as unsightly, distracting from the magnificent urban architecture, and they were actively fought against. At the turn of the century, highly toxic compounds such as arsenic were commonly used, such as in the infamous “Eureka weed killer” below. The progress of the chemical industry after the First World War lead to the development of new weeding chemicals. Introduced in 1944, 2,4-D (2,4-Dichlorophenoxyacetic acid) was used extensively in New York and other American cities to kill dandelions in lawns or ragweed (a well-known allergy-causing plant). 2,4-D was promoted by chemical companies as a “magical” way of “improving the appearance of home and public recreation areas”. The discovery and introduction of the even cheaper glyphosate in the 1970s made weeding accessible to everyone, local authorities or domestic gardeners.
As a result of the widespread use of weedkillers since the 1950s, today’s urban residents have become used to mineral cities. They may visit parks, tend to a garden or enjoy the presence of street trees, but spontaneous, non-chosen plant growth is seen as “abnormal“, an “eyesore”. In France, where glyphosate has been banned, plants have started to grow back along walls, in pavements and gutters. Some residents are pleased to see nature being allowed to thrive, others are horrified by this “neglect”.
This “push and pull” for or against weeds is not new. In the 19th century, when Paris was being heavily remodelled and urbanised, artists and writers complained about the disappearance of the city’s romantic character. In the 1970s, as American cities were clearing streets and abandoned spaces with thousands of liters of glyphosate, the hippie movement rejected this call for tidiness. Throughout history, spontaneous plant growth has been rejected, sometimes for economic (lower yield) or safety reasons (for example, toxic seeds in cereals, or trees lifting paving slabs), but more often for aesthetic reasons. As humans, we like pruning and weeding because we have a certain unconscious fear of nature “taking over“. We created pavements, and stone walls and buildings, but we have no control over what seed may germinate in a pavement crack.
Across Europe, more and more cities are moving away from chemical weeding, and sometimes from weeding altogether. While it is impossible to completely stop weeding, I believe that all cities should be able to move away from traditional “blanket” removal methods. We talk a lot about rewilding our countryside, we read articles about the extinction of plants, insects and other animals. Should the rewilding of our cities not be seen as essential too? Far from being dangerous and unsightly, our spontaneous flora may be a first step needed to heal our broken relationship with nature…only time will tell.