Μake us preferred on Google The view from above Hyde Park is startling.
What should be one of London’s great expanses of summer green has turned the colour of straw: broad stretches of yellow and brown grass broken only by the darker green of trees and the occasional patch that has managed to withstand weeks without meaningful rain.
On Thursday, August 13, the mercury was climbing towards 36C once again, with temperatures above 36C already recorded near Gatwick Airport and the Met Office warning that some parts of England could reach 38C.
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London’s parks, gardens and playing fields are bearing the unmistakable visual imprint of an extraordinary summer.
An image taken from a police helicopter captures the scale of the transformation. From the air, the capital’s familiar green spaces appear almost bleached.
Britain has now endured its fifth heatwave of the year. On Wednesday, temperatures exceeded 34C for the sixth consecutive day – a run not seen since 1961.
An amber extreme heat warning has been extended further west, while hospitals are experiencing what health workers describe as their busiest summer ever.
And the Met Office has warned that this summer is on course to be the UK’s hottest since records began.
But what has happened to the grass? Has London’s famous greenery actually died?
The yellow lawn may be deceiving
The answer, according to scientists and horticulturalists who spoke exclusively to TO VIMA, is reassuring: in many cases, the grass is not dead at all. It has simply gone dormant.
“The yellow grass across London looks dramatic, but much of it is likely to be dormant rather than dead,” said Yadvinder Malhi, Professor of Ecosystem Science at the Environmental Change Institute at the University of Oxford.
“A crucial point is that grasses grow from their base, rather than from the tips of their leaves, so even when all the visible foliage has turned brown, the plant can still be alive. As long as the growing points at the base and the roots remain intact, recovery can be remarkably quick.”
The survival strategy is relatively simple. As conditions become increasingly dry, grass slows its growth and conserves water. The outer leaves curl, dry and eventually die, while the plant protects its growing points and roots beneath the surface.
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“If, for example, we had several days of substantial rain in late August, we could see a significant greening of the parks within a few weeks,” Professor Malhi said.
There are limits, however. “The areas that may not recover so readily are those where prolonged drought, perhaps combined with heavy footfall on very dry ground, has actually killed or seriously damaged the plants.”
A problem for wildlife as well as gardeners
Professor Alistair Jump, Dean of Natural Sciences at the University of Stirling, said the phenomenon was a familiar response to prolonged heat and dryness – but the scale of this year’s event was unusual.
“The yellowing of grass currently seen across parks and gardens in much of the UK occurs routinely in response to periods of prolonged hot dry weather. Often this response is quite localised but this year the prolonged and widespread drought has led to large swaths of the landscapes in our towns and cities and across the countryside turning yellow.”
The consequences extend beyond appearances.
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“This has a big impact on food and shelter for our wildlife – and that impact can be particularly acute in towns and cities. Typically, when the grass yellows, the roots and seeds survive and the grass cover recovers when rains return, but some grass species are more susceptible to prolonged drought than others.”
The challenge, Professor Jump said, is that such weather may no longer be exceptional.
“Our climate is changing rapidly and we see these sorts of prolonged hot dry spells becoming more frequent and intense. This may mean that we will need to shift to using different mixes of grass species for our parks and changing the way that we manage them to encourage greater resilience of the plant cover.”
That adaptation matters because London’s parks are not merely recreational spaces.
“Adapting the management of our parks and gardens for the new climate is of critical importance because they provide a refuge, not just for people gaining the many benefits of access to greenspace, but also because in towns and cities they provide vital habitat for a wide range of biodiversity that lives alongside us and helps those urban ecosystems function.”
‘Green lawns will return – until the next drought’
Chris Thomas, Professor of Biology and Biodiversity at the University of York, offered a similarly reassuring assessment.
“Hiding inside the curled brown leaves of the grass are living tips of the grass, waiting for the return of rain to start growing and convert brown back to green. Grass is generally pretty good at this, although it may be a bit patchy for a while. Don’t fear – green lawns will return, until the next drought that is.”
Yet Professor Thomas believes the debate should go beyond whether Britain can restore its traditional green lawns.
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“Whether we Brits should continue to aspire to have plain green grass expanses across our lawns and parks is another matter, rather than wildflower meadows and deeper rooted shrubs, but changing a nation’s attitude to their gardens is not something that is easy to achieve!”
Kew: ‘We can’t justify irrigating swathes of grass’
Joe Richomme, Botanical Horticulturist and Gardens Supervisor at the Royal Botanic Gardens, Kew, said London’s park grass was proving remarkably resilient.
“The vast majority of London’s park grass is actually highly resilient to drought. Even having had no water at all for the last six weeks the grass is still alive, just dormant, waiting for more favourable conditions. With the first extended rainfall it will start to green back up again.”
For Richomme, the change is principally aesthetic – and that may require Londoners to rethink what a summer park should look like.
“The change we’re seeing is largely aesthetic, so it may be a case of adapting our expectations of how our parkland will look in periods of drought. Water is a finite resource, and we can’t justify using it to irrigate swathes of grass which we know will bounce back.”
The answer may lie in changing both the species planted and the way they are managed.
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“Some grasses are naturally better adapted than others, and there’s work to be done in selecting a diverse mix of species that will cope well with these kind of conditions. We can also look to make changes to how we’re managing some of our grass areas. Leaving grass to grow longer can make it more resilient to drought, for instance.”
Such changes could have an unexpected benefit.
“Both of these measures can also boost wider biodiversity, so there’s potential in having to adapt to these challenging conditions.”
London’s parks may never look quite the same
For Professor Malhi, the yellowing of Hyde Park and other London green spaces is therefore more than a temporary curiosity. It could be a glimpse of a new normal.
“If hot, dry summers become increasingly frequent, as climate projections suggest, Londoners may have to become accustomed to parks that are yellow or brown for part of the summer rather than the consistently green landscapes traditionally associated with southern England.”
London’s future climate, he said, may increasingly resemble that of places much further south.
“London’s climate is expected to become increasingly characterised by hotter, drier summers, bringing some aspects of its summer conditions closer to those now experienced in northern Spain.”
That could force a change in both horticulture and public expectations.
“The climate of the coming decades will be different from that in which London’s nineteenth-century parks were managed, and our expectations of what a healthy urban landscape looks like in summer may have to change with it.”
For now, however, London’s yellow grass is waiting.
The roots are still there. Beneath the curled, scorched leaves, the living tips are conserving what little moisture remains, ready for the rain.
When it finally comes, Hyde Park may begin turning green again almost as quickly as it turned yellow.
The more difficult question is how many more summers Britain can expect to pass through before yellow becomes the new green.
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