Most gardeners love nothing more than the chance to chat about what has worked and what hasn’t in their flowerbeds this year.
So the latest callout from the Royal Horticultural Society will be music to their ears; the RHS is asking for information about what flowered for ages, what loved being waterlogged and how plants did on the occasional hot day, so that they can draw up a plan for how to keep gardening alive during the climate crisis.
Heatwaves and a drought in 2022 and the wettest ever 18 months between 2023 and 2024 have meant that gardens are either roasting or turning into bogs.
Plants that have been a taken-for-granted fixture in flowerbeds for centuries may have to be swapped for new species, or made more resilient to the climate crisis.
The RHS has already noticed that Gladiolus and Iris are thriving in the warmer summers, but others, including Hebe and Pittosporum, are being negatively affected by the increasing amount of heavy rainfall, extreme temperatures and unpredictable frosts.
Working with the Universities of Sheffield and Reading, the charity is trying to understand what is growing well or struggling, how different gardeners are coping with the climate crisis and which maintenance habits are working and which are not. The research will also build up a picture of which plants are thriving in different parts of the UK, and which are not.
The research will help to inform recommendations for how to manage and protect plant diversity across the country. Information will also be used to identify which plants might thrive in the UK in the future.
The RHS is already swapping out some plants for others in its own gardens. Heat-loving banana and lotus have flowered at RHS Garden Harlow Carr in Yorkshire, which was not thought to be possible a decade ago. Lagerstroemia, originating from south-east Asia, has been trialled successfully at RHS Garden Wisley in Surrey, which also would not have been likely before the UK’s climate began to change.
RHS Garden Hyde Hall near Chelmsford in Essex has managed to grow cacti due to the warming conditions. The plants have overwintered without any protection and have withstood the very wet spring. Hyde Hall are also now able to grow euphorbia mellifera outside in their Australia garden, which normally overwinters indoors in their historic glasshouse.
Gardeners are having to duplicate and move some plants from Wisley, which is in one of the drier, hotter parts of the country. Heather and Hepatica plants from the national collections also based at Wisley are being grown at other sites because of vulnerability to drought and the potential for loss.
Tim Upson, RHS’s director of gardens and horticulture, said: “In a garden, plant diversity is everything and our extensive collections provide some insight into what grows well from year to year and from place to place. Tapping into the observations of the UK’s 30 million gardeners, many of whom will have noticed longer-lasting blooms or waterlogged perennials, will help us in better understanding how our gardens need to evolve to ensure they continue to provide the environmental and health and wellbeing benefits we currently enjoy, 10, 20 and 30 years from now.”
Gardeners can contribute to the survey, which runs until 15 October, here.
• The picture on this article was changed on 1 August 2024 because an earlier image showed a succulent rather than a cactus.
