As autumn settles across the northern hemisphere, trees are putting on vibrant displays of russet, orange, and gold, marking the traditional start of the tree planting season. Experts emphasize that the best time to plant is during the trees' dormant winter phase. However, with shifting climate conditions, questions are emerging about which species will thrive in the future.

At Hever Castle in Kent, head gardener Neil Miller and his team plant between 50 and 60 trees annually from autumn through early spring. This year, their focus includes rethinking tree selection to adapt to changing environmental stresses. The castle is hosting seasonal events highlighting autumn foliage and featuring talks by respected arborist Tony Kirkham, who addresses the challenges of tree establishment and long-term survival.

Kirkham cautions that newly planted trees—those under ten years old—lack an extensive root system and thus require supplemental watering and attentive care regardless of species. He notes that no tree is completely drought-tolerant during its establishment phase. Additionally, rising summer UV levels have been impacting certain species; for instance, sycamores have experienced leaf browning and premature drop this year, although a wetter winter should help them recover. In contrast, persistent browned leaves that remain on a tree can signal more serious distress.

Native oaks have fared relatively well, likely due to their deep root structures. Still, Kirkham advocates broadening planting choices to include non-native species better suited to anticipated climatic conditions. Projections suggest that by 2050, the UK’s climate may resemble that of present-day Barcelona, prompting consideration of trees from regions such as the Caucasus and eastern North America.

Species from the cypress family, including Taxodium, demonstrate resilience to hot summers and waterlogged soils in winter. Trees like liquidambar (sweetgum) offer desirable shade and vivid autumn colors, while red oaks and black walnuts provide robust, long-lived canopy options capable of tolerating a wide range of weather extremes.

Miller adds practical recommendations, highlighting the Persian silk tree (Albizia julibrissin), known for its mimosa-like foliage and summer blossoms, as well as crape myrtle (Lagerstroemia indica), native to China and the Himalayas, which produces striking pink, purple, or white flower clusters.

Despite the uncertainties of weather patterns, Miller encourages tree planting efforts, reminding the public that natural cycles prevail and adaptation is essential. With careful species selection and attentive management, trees will continue to play a vital role in mitigating heat and sustaining the landscape.