It’s easy to imagine what rewilding the countryside might look like, but harder when it comes to cities. In ‘Feral’, George Monbiot lists the species that once roamed the UK, pointing out that when Trafalgar Square was excavated, the gravels were full of hippopotamus bones.

The idea pushes us. Do we want to see hippos before we head into the National Gallery? How about chasing after butterflies down Oxford Street? Where is the bold thinking in the UK, like Paris saying yes to swimming in the Seine?

Thamesmead in the 1960s was designed to give children from cramped homes in East London the best possible childhoods, providing adventure on their doorstep. Nature was central. The original designers for Thamesmead may not have described their approach as biophilic but it was, because they were enabling a wilder state for the human spirit. Biophilia is about health and wellbeing and happiness and reaches back to the origins of the human species and the instincts essential to our survival and success, such as refuge and discovery, risk and reward. Now Peabody, who are regenerating the town, are reaching back to a framework of living in the landscape.

Separating ourselves from nature is at the root of our current crises. The biodiversity crisis is a tale of decline over thousands of years, from hunting mammals to extinction to poisoning birdlife with pesticides. But estrangement is being entrenched by an urban environment that is vehicle dominated and highly controlled. In places, residents are even fighting councils to hold onto a few plants in pots tucked away on their estate walkways.

At the same time, we demand ever more of this urban environment. With new open spaces, people want to see planting maximised, and room made for play. They need be hard wearing and easy to maintain, integrate art and artefacts, generate income, support local business, and host events, activities and installations.

With such conflicting priorities, it can help to take a biophilic approach. When we recognise that humankind and nature are part of one single system, objectives can be balanced in a way that is mutually inclusive and beneficial.

What if every project was conceived from the start as purely green and blue space into which other required elements are then inserted, and also designed specifically to co-exist with nature? So, for example, play and adventure can be incorporated through a rope bridge walkway on a causeway with wild and natural planting either side.

When it came to the restoration of Battersea Power Station, it could have just been about the building. But the story has become so much bigger because of the landscape. So, we find ourselves talking about play and community, about falcons nesting on a chimney, and 95 species of birds: about a moat of grasses, verbena and red-hot pokers.

In an age of extinction, we need a bolder response than greening—we need wilding. We need to seize every opportunity to move back from the edge. Cleaning rivers like the Seine to make them fit for swimming means they start to teem with other life too. We need every space to work hard, not least the myriad wasted and leftover spaces all around us such as over-sized highway space, and mown grass with limited purpose. As storms and heat islands become more intense, we need nature-based solutions to slow and store the water.

This demands a new environmental aesthetic, allowing nature to colonise everywhere. We should champion weeds as the darling plants of our age, from the drought tolerant purple toadflax to the delicate and irresistibly delicious wild strawberry. Their vigour may not look pristine but it will look ever more beautiful as we retune our minds away from tidiness and to delight in ecological health.

Wilding gives us permission to think differently, and it requires more, not less, skill and knowledge. It sets ambitions high and protects nature from value engineering, by making it impossible to continue seeing nature primarily as a pretty backdrop.

Wilding is about way more than plants. The deepest purpose of wilding the city, and the biggest challenge and most important role of landscape architecture, is to heal the broken connection between people and nature.