Urban gardens strategy needed for new homes

More than four fifths of the UK population live in urban areas, often with limited access to nature. With this in mind, ensuring that domestic and shared gardens are created and maintained in new developments will be fundamental in building resilient communities.

Gardens and the cultivated plants within them offer effective and low-cost nature-based solutions for climate adaptation and mitigation. Just to name a few, these include slowing the flow of rainwater to reduce flooding, cooling to reduce temperatures in urban areas, and capturing pollution to improve air quality and human health.

Gardens also provide a crucial home for wildlife. RHS scientific research has shown urban gardens to be invaluable to pollinators, on whom we depend for food security and whose plight has been underlined by the recent declaration by Butterfly Conservation of a butterfly emergency in the UK after observed numbers reached a record low. Urban gardens are a critical stronghold for the UK’s endangered hedgehog population; a species that is rapidly becoming nearly as rare as the red squirrel in Great Britain and relies on well-connected garden habitats for survival. 

The benefits of gardens for people, in particular for health and wellbeing, are diverse and well documented. These include the mental health benefit of being able to be close to and engage with nature, the physical activity benefits of gardening as an excellent way to exercise, the economic benefit to householders of being able to grow their own food, and the social benefit of promoting community activities and social engagement through shared garden spaces.

• The shoehorning in of gardens where space is lacking to strengthen urban resilience, such as in Athens, where disused railway lines, bridges and stations are being used to help mitigate the urban heat island effect and provide important corridors for the movement of pollinators.

• The development of rooftop greenhouses on commercial high rises in Seoul for urban farming, which also reduce greenhouse gas emissions via the exchange of energy between office and growing space.

• The installation of new green walls as part of the re-development of Turin, which helped to provide all important ecosystem services in a dense urban environment, including pollution capture, and showed that minimal urban greening interventions have a substantial impact on citizens’ wellbeing.

Research by RHS Science has been demonstrating, and will continue to focus on, identifying which plants can help to futureproof towns and cities. This includes identifying the role of hedges in improving air quality, what garden trees will withstand a changing climate and provide essential ecosystem services, how water can be managed and retained in gardens, and the science of green behaviours.

Professor Alistair Griffiths, RHS Director of Science and Collections, says: “With plans for a once in a generation housebuilding spree, it is time for a collaborative and coordinated strategy that puts gardens and cultivated green spaces at the heart of our communities, leveraging their numerous benefits for many more people and providing space for active and not simply passive engagement with nature.”

The call on Government is clear: gardens are critical to the environment, biodiversity, and human health and wellbeing. The RHS asks for updated planning guidelines to require cultivated landscapes, garden masterplans for urban areas, and a review of the Biodiversity Net Gain 4.0 metric. 1.5 million new homes should translate to 1.5 new garden access opportunities, implemented via an effective and collaborative strategy for the creation of domestic gardens and the creation and maintenance of shared garden spaces.