Hotter Summers Force RHS to Move Hydrangeas North 2026

Hotter summers and intensifying heatwaves are forcing the Royal Horticultural Society (RHS) to move its hydrangea collection from southern England to northern gardens, a shift that highlights how climate change is reshaping British gardening. With lush blooms and soil-dependent colors, hydrangeas have long thrived in the UK's mild, damp climate, but rising temperatures are now threatening their survival in the south.

The RHS, which has over 600,000 members, has seen inquiries about drought and heat damage to hydrangeas more than triple since 2023. Hydrangeas rose from the seventh to the first most frequently reported plant for hot weather problems by 2025, and they remain the top concern in 2026. This data-driven alarm has prompted the charity to consider relocating its prized collection from Wisley in Surrey to its gardens in Greater Manchester and North Yorkshire, where conditions are expected to stay cooler and wetter.

Why Hydrangeas Are Vulnerable to Heat

Hydrangeas, particularly the Hydrangea macrophylla types (mophead and lacecaps), are especially sensitive to hot, dry conditions. Their large leaves lose water quickly, and sandy soils like those at Wisley exacerbate drought stress. In contrast, Hydrangea paniculata varieties are more resilient, tolerating sunnier spots if the soil retains moisture.

Guy Barter, chief horticulturist at the RHS, explains: “Hot dry summers are not the best for hydrangeas, although it is mainly the Hydrangea macrophylla types that suffer most, especially in sunnier sites and sandy soils such as we have at Wisley.” He adds that in light shade or north-facing slopes, hydrangeas remain fantastic plants, but gardeners must be more selective about planting locations as the climate warms.

Climate Data and Gardening Trends

The RHS’s gardening advice service has tracked a dramatic increase in heat-related queries. In 2023, hydrangeas were the seventh most reported plant for drought issues; by 2025, they topped the list. This trend reflects broader climate shifts, with UK summers becoming hotter and drier, particularly in the south. The RHS’s northern gardens in Bridgewater and Harlow Carr offer better soil and a superior climate for hydrangeas, making them ideal new homes for the collection.

What Gardeners Can Do to Protect Hydrangeas

For home gardeners facing hotter summers, the RHS recommends several strategies to keep hydrangeas healthy. Choosing the right variety and planting location are critical, but ongoing care also matters.

• Plant in partial shade or north-facing spots to reduce sun exposure.
• Mulch generously to retain soil moisture and cool roots.
• Water deeply but less frequently to encourage deep root growth.
• Select resilient varieties like Hydrangea paniculata over macrophylla.
• Improve soil with organic matter to boost water retention.

These steps can help hydrangeas survive even in southern gardens, though moving them north may become necessary for long-term preservation.

The Future of Hydrangeas in the UK

As the RHS relocates its collection, it sends a clear signal to gardeners: climate adaptation is no longer optional. The shift to northern gardens is not just about hydrangeas—it reflects a broader need to rethink what we plant and where. With more than 600,000 members, the RHS’s actions influence gardening trends nationwide, encouraging a move toward more heat-resilient landscapes.

While this news may disappoint southern gardeners who love hydrangeas, it also opens opportunities to explore other flowering shrubs better suited to warmer conditions. The RHS’s research at Bridgewater will continue to provide valuable insights into hydrangea care under changing climates, ensuring these beloved plants remain part of British gardens for generations.

FAQ

As climate change continues, gardeners must adapt. Whether you’re relocating plants or changing care routines, staying informed is key. The RHS’s proactive approach offers a model for preserving beloved species in a warming world.