Robert and Didi’s allotment garden plot in Kirtlington, Oxfordshire, United Kingdom
Allotment or community gardens (like the one pictured above) are a common feature of many European townships. In the United Kingdom, these are collections of small plots that can be rented for a small fee by individuals to grow food. Mostly cultivated by hobby gardeners, these patches are sites of experimentation with a variety of crops – many more varieties than a conventional, commercial farm would dare to grow! Allotments are wonderful spaces of ‘agrobiodiversity’- the sheer diversity of food crops including leafy and root vegetables, fruits and occasionally cereal grains. On the day the above picture was taken, we harvested a unique variety of curly lettuce on Robert and Didi’s allotment and made delicious salad out of it. There are other vegetables, raspberries and even a small vineyard on the plot – an impressive variety of species on a tiny piece of land in a semi-rural corner of England! Most allotment gardens are a mosaic of small plots, each very individual in its soil type, planting design and crop varieties. This inevitably means that some plots remain uncultivated at times and they can accumulate ‘weeds’ very quickly. Some of the weeds (brambles, in particular) are terribly difficult to get rid of and leave many gardeners frustrated while others are benign.
Somewhat counterintuitive to the frustration with weeds, the headline of report published earlier this week in Nature says: “Weeds warrant urgent conservation”. To many conservationists, that sounds blasphemous: Weeds and conservation? No way! But this report is based on a global analysis of ‘conservation gaps‘ in wild relatives of our 29 most important crop species. There are about 455 known wild relatives of these crops and more than half of those are underrepresented in gene bank collections like the Millennium Seed Bank at the Kew Gardens. But why worry about those so-called ‘weeds’ which grow in the wild and often end up making life difficult for gardeners and farmers. Well, these weeds are the ones that have the ‘magic formula’ to grow in harsh conditions like too little water or too high temperatures (or in case of bramble, ability to send it’s tough roots so deep in the soil that without a JCB digger, the gardener has to accept defeat!). But what is remarkable about these plants is their tenacity. And this tenacity is what might help us in the future to make our crops resilient. That is why the report says we might have to turn to ‘weeds’ to make our crops stronger. If we are successful in expanding our portfolio of crops from 29 to 455, that’s a big step in making agriculture resilient.
This reports has some important consequences for how we grow our food in the Anthropocene – a geological age of our own making. The Anthropocene demands innovative ways to tackle a variety of challenges and food security is one of the more serious ones. There is no doubt we need to increase production to feed a growing population, a proportion of which will also become more affluent. But the question is: can we continue to depend on the 29 crops or are we better off spreading the net wider and looking at their 455 wild relatives? These ‘wild cousins’ might well include some rowdy, unruly and rambunctious characters, but sooner or later we will have to look at their good qualities. To paraphrase Ralph Waldo Emerson, the 19th century American Transcendentalist, weeds are plants whose virtues have not yet been discovered. The challenge for us in the Anthropocene is to discover the virtues of these 455 wild cousins and feed 9 billion people by mid-21st century.