Do the trees we plant today fit tomorrow’s climate?
In the landscaping industry today, one question is becoming increasingly difficult to ignore: are the tree species we’re planting today suited to the climates they’ll experience in the decades to come? For nurseries, landscape architects, contractors and local authorities alike, this is no longer a theoretical discussion, but a practical consideration in how we plan, grow and specify trees for future landscapes. At Hillier Trees, we’ve held conversations with customers covering this shift over the past few years.
Last year in particular, a questionnaire was sent out to clients across the landscaping and public realm sectors that painted a clear picture: Not only is there growing interest in climate-resilient tree species, but there is also a strong desire for decisions to be grounded in evidence rather than speculation. Designers and contractors today are increasingly asking nurseries to focus on the bigger picture and understand how species will perform not just in today’s conditions, but also in the next 30, 50 or even 100 years. The truth we found is that the climate itself is already sending clear signals.
What the climate is telling us
In January alone, our field tree production operations at Andlers Ash recorded approximately 239mm of rainfall within a single month. Across the nursery’s 500 acres of field-grown trees, this equated to around 107 million gallons of water falling across the site in just four weeks.
Significant shifts in the climate such as this illustrate how weather patterns are becoming more extreme and less predictable. While heavy rainfall is one side of the equation, many parts of the UK are also experiencing longer periods of drought and heat stress during the summer months. For growers and landscape professionals, these changing conditions reinforce the importance of understanding how different species will perform over time.
Taking a science-led approach
To better understand how future climate conditions may affect tree suitability within the UK, we commissioned a study with Urban Plant Lab that examined seventeen commonly planted landscape tree species across 23 UK cities, analysing their current climatic suitability alongside projected future conditions using plant trait data, global species distribution records and climate modelling.
The results from the findings suggest that the outlook for many of the species currently used in UK landscapes remains positive. In fact, most of the species assessed demonstrated moderate or high suitability for both current and future climate conditions.
However, the research conducted also emphasized that climate change won’t have a universal effect on the UK. Instead, every region within the country will suffer in various ways, with northern and western areas expecting to remain broadly suitable for many existing species, while parts of the south-east may experience greater pressure as temperatures rise and summer rainfall becomes less reliable.
Additionally, the study also suggests that species such as Betula pendula, Prunus avium and Tilia cordata may become increasingly vulnerable in Southeast England towards the end of the century, highlighting the importance of considering regional differences when planning future planting.
Trialling the next generation of trees
Alongside the work we’ve put into our operations following this study by Urban Plant Lab, we’ve also been carrying out our own production trials over the past three years, evaluating species that aren’t currently a part of our commercial growing programme but may have potential for future production. As with any trial programme, some species have performed well while others have presented challenges in terms of growth rate, form or propagation.
But identifying species that may be suited to future climates is only part of the equation, as those trees must also be commercially viable to grow in UK nurseries, capable of being produced at scale and delivered to the market at the sizes required for landscape projects. Simply importing unfamiliar species from Southern Europe is unlikely to provide a reliable long-term solution if those trees cannot be successfully grown and supplied within the UK nursery system.
Research through collaboration
In the end, developing a climate-resilient tree supply will require collaboration across the entire sector. Fortunately, many world-leading research institutions within the UK are doing just that, studying plant science, urban forestry and climate change in detail. By bringing together researchers, commercial growers, landscape professionals and local authorities, the industry can develop practical solutions that can be delivered at scale.
Continued government support will also play an important role in enabling the research and trials needed to expand the range of viable tree species available to the market.
Working with clients and communities
At Hillier, we’re currently working with several clients on projects where the boundaries of traditional tree selection are being explored, enabling us to trial promising species within real landscapes while gathering valuable feedback on how they perform in different environments. As part of these efforts, we also recently partnered with Tree Musketeers, who are planting trial species across residential estates and public green spaces.
Projects such as these help researchers understand how newer species perform in urban environments while also engaging local communities in the long-term stewardship of their urban trees.
Looking ahead
The question of whether the trees we are planting today are fit for tomorrow’s climate doesn’t have a simple answer. While evidence suggests many of the species currently used in UK landscapes will remain viable for decades to come, climate change is also likely to reshape growing conditions in specific parts of the country, meaning diversification and forward planning will become increasingly important. For the landscaping industry, the key will be maintaining a balanced, science-led approach and continuing to plant proven species; all while gradually introducing new ones that may build resilience for the future.
Most importantly, these conversations need to start early. Engaging with nurseries during the planning stages of major landscape projects allows time to consider species selection, availability and potential contract growing opportunities. Because when it comes to trees, the decisions we make today will shape our landscapes for generations.
