‘Embrace the bog’: Chelsea flower show expert champions flood-proof garden

<span>The Flood Resilient Garden at RHS Chelsea, designed by Naomi Slade and Ed Barsley.</span><span>Photograph: Sophia Evans/The Observer</span>
The Flood Resilient Garden at RHS Chelsea, designed by Naomi Slade and Ed Barsley.Photograph: Sophia Evans/The Observer

Gardeners should “embrace the bog” that has formed in backyards across the country after record rain, a designer at this week’s Chelsea flower show has said.

Naomi Slade will unveil her design for a floodproof garden on 21 May, showing that even with the unusually wet weather seen in recent months, British gardens can still be full of colourful flowers.

The Flood Resilient Garden, which will be open to the public this week at RHS Chelsea, was designed by Slade and Ed Barsley, who will be purposefully flooding their patch of the showground to demonstrate the best of bog planting.

“The rain has been a real problem,” said Slade. “As a garden designer, everyone has been talking to me about it. Extreme weather events affect us gardeners very badly. We have just had one of the wettest winters in memory, and it has impacted everyone from growers and nurseries to domestic gardeners, who have noticed their gardens have just become thoroughly boggy.”

According to the Met Office, England saw a record amount of rainfall in the 18 months to March, with about 1,695.9mm of rain falling from October 2022 to March 2024, the highest level since records began in 1836.

But Slade is trying to show that a boggy area of garden can be a boon, showcasing bright blooms including buttercups, ragged robin and primula. “People need to embrace the bog,” she said. “If you have a boggy bit, you should plant things that really like it. A lot of pond marginals are tolerant of a wide range of conditions. Just because it’s a bog plant doesn’t mean it needs to be absolutely wet all the time; a lot of them put on growth in spring and are almost dormant over summer.”

Speaking as she constructed her garden in the run-up to Chelsea, she said: “It is just a riot of colour. It’s about changing minds and changing perceptions. I have colourful flowers – pinks, sky blues, oranges, yellows and some brick-red in there.”

The garden works by embracing water as a feature, and harnessing it for later use. The designers have created dense planting arrangements to slow the flow of floodwater, and an elevated mound to plant species which aren’t as fond of being submerged. It also contains a central swale that forms a stream, channelling rainwater into a feature pond, and large water tanks that double as ornamental ponds and which store water for later use. Smart technology drains the water butts ahead of heavy rainfall so they can be filled again.

Slade said: “We have a mound and a big dip for the water to run down. Experienced gardeners know that if you have a less than favourable condition, if you build a mound you can elevate the roots out of the water. So you can still grow your fruit trees, roses and dahlias. They look at their lawn, that is essentially a bog, and think: if we build a mound and elevate the roots, the sensitive plants can survive.”

Storing water in the garden is good for the wider environment too, Slade said: “There’s lots of concern at the moment about sewage [discharging] into rivers due to heavy rain.” If gardeners can capture heavy rainfall in containers, it reduces the amount running into drains and overwhelming the system, she said.

Paving stones will not be a feature of the Flood Resilient Garden. Water runs off them and is not absorbed by the soil below, contributing to flooding, Slade explained. “I recommend paving as little as possible. Of course, you need surfaces that allow you to access your garden, but there has been a habit of covering areas in terracotta or ceramic tiles or concrete, and water just runs off. It adds to the problem. Recognising you need to make space for water will make all the area around it more accessible. Also consider stepping stones, or gravel with plants growing in it. Covering soil with concrete is always going to be a bad idea.”

With the extreme weather caused by climate breakdown, gardeners will have to adapt and change with the seasons a lot more, Slade said. “We need to get out of the idea that our gardens are static – there should be dynamism within gardening.

“The traditional view is that your garden would always look the same, only changing in summer and winter, with homogeneous, mass-produced plants.

“But now we have a new younger generation of gardeners who are very environmentally aware and want to make a difference. We want to give them knowledge, agency and information so they can plant climate-friendly gardens which are resilient to extreme weather.”