The great British cup of tea could become harsher, more expensive and less reliable as climate change disrupts the growing conditions on which its familiar flavour depends, according to a new report.
The analysis, published by Christian Aid, finds that rising temperatures and increasingly unpredictable weather are already altering the chemistry of tea leaves in key growing regions across Kenya, India and Sri Lanka.
The result, scientists warn, is not a single dramatic change but a creeping shift towards greater variability and, at times, noticeably more bitter and astringent flavour.
Tea quality depends on a carefully balanced mixture of compounds such as catechins, amino acids and polyphenols, that determine flavour, aroma and mouthfeel. Higher temperatures tend to increase the production of more astringent compounds while reducing those associated with sweetness and balance.
Extreme weather places tea plants under additional stress, altering how they develop, while rising temperatures are also expected to spur growth in pest populations, adding further pressure on crops.
Dr Neha Mittal, senior climate services scientist at the Met Office and visiting scientist at the University of Leeds, said: ‘Tea brands depend on delivering a stable and recognisable flavour profile. As climate variability increases, achieving that consistency becomes more challenging.’
The impact is already being felt by farmers on the ground. Reuben Korir, a small-scale tea grower in Kericho County, Kenya said: ‘When the weather is very dry or unpredictable, the tea quality changes. The leaves are smaller, and we believe the taste is not as good as it used to be during more stable seasons. Rains no longer come when expected, and dry periods last longer. Harvests are not predictable anymore, and neither is the income.’
Beyond flavour, the report highlights growing instability in global tea markets. Climate shocks including droughts, floods and heatwaves are already disrupting harvests and pushing up prices. Geopolitical pressures affecting energy markets and key shipping routes are simultaneously increasing the cost of fertiliser, fuel and transport. The report describes these converging pressures as a ‘perfect storm’ likely to increase volatility in both the price and quality of tea reaching British shelves.
The UK drinks approximately 100 million cups of tea each day, and around half of its tea imports come from Kenya, leaving British consumers significantly exposed to climate disruption in East Africa.
Claire Nasike Akello, Climate Adaptation and Resilience Lead at Christian Aid, said: ‘What we are seeing is the beginning of a shift towards a harsher brew, with the risk that Britain’s favourite drink becomes more bitter, more expensive and less reliable.
‘But this is not just about what is happening in our kitchens or in our mugs. The biggest impact will be felt by the people growing and processing tea, many of whom are already facing rising costs, more unpredictable harvests and worsening insecurity.
‘Climate change is amplifying deep-rooted inequalities in the tea sector. Farmers and workers who have done the least to cause the climate crisis are being pushed further onto its front line, with fewer resources to adapt.
‘Protecting the future of tea means investing in people as well as crops – through fair pricing, targeted adaptation finance and stronger support for farmers and workers.’
Photo: Yana
