- Climate change, with drier soil and reduced water availability, threatens over half of Kew Gardens’ 11,000 trees by 2090.
- The urban heat island effect from London’s dense infrastructure exacerbates the nighttime temperatures.
- Kew plans to introduce resilient species from regions like Iran, Azerbaijan, and the southwestern United States to mitigate tree loss.
Amid the beauty of Kew Gardens, a UNESCO World Heritage Site since 1759, lies a threat: climate change could decimate thousands of trees in the coming decades.
Experts at Kew have used climate modelling to reveal that over half of the gardens’ 11,000 trees may perish by 2090 due to drier soil and reduced water availability. The urban heat island effect, caused by London’s dense infrastructure, worsens the situation by keeping night-time temperatures higher than in rural areas.
Kevin Martin, Kew’s head of tree collections, noted that Kew is about 3 degrees Celsius warmer than in the 1980s. Native species like the English oak (Quercus robur) face particular risks. A severe drought in 2022, with record temperatures reaching 40 C (104 F) around London, killed 400 trees at Kew, highlighting the urgent need for more resilient species.
Kew Gardens houses 8.5 million plant and fungal specimens from around the globe. Plant material from the Hyrcanian forest of Iran and Azerbaijan, the steppes of Eurasia, the southwestern United States, and parts of continental Europe could offer solutions. These species, known for their resilience to climate extremes, could provide a blueprint for urban planners worldwide.
Martin, who plans to travel to Georgia in September to collect seeds for Kew, emphasised the importance of these efforts: “It’s going to be vitally important, not only for our generation but for the next generation,” he said, standing beside a 124-year-old weeping beech (Fagus sylvatica ‘Pendula’) already showing signs of decline.
The report published last week details the findings and proposed solutions, offering hope for the future of Kew Gardens and urban green spaces worldwide facing climate change.