British cup of tea under threat as climate change could fundamentally alter its taste, campaigners fear

Even tea growers in the UK are experiencing climate change, which they warn is making it much harder to achieve consistent flavours.

Disruptions to harvests caused by the changing climate are likely to cause price spikes, rising costs and unreliable supplies of the staple British drink.

Tea flavours and quality depend on a balance of compounds such as catechins, amino acids and polyphenols, according to the report.

However, higher temperatures increase the production of more astringent compounds while reducing sweetness, leading to a more bitter taste.

Erratic rainfall can dilute compounds that give tea its depth and character, while extreme weather from droughts to floods and worsening crop pests in warmer conditions can also put pressure on the plants, leading to lower yields, lower quality and more bitter crops, the report says.

It carried on: "The result is a simple but unsettling prospect, the familiar taste of the British cuppa, smooth, balanced, reliable, is becoming harder to guarantee."

Reuben Korir, a small-scale tea farmer from Kericho County in Kenya, said that when the weather was very dry or unpredictable, the quality of the tea changed.

He said: "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.”

Even in the UK, the changing climate is a problem for tea producers, they say.

Lucy George, who runs Peterston Tea, a small tea farm in South Wales and one of the first commercial tea farms in the UK, said: "Seasons are less predictable with warmer winters, sudden late frosts, and irregular rainfall patterns.”

For the farm, warmer periods could accelerate growth, while erratic rainfall or cold snaps could slow growth and affect leaf structure.

She continued: "The balance that gives tea its depth, sugars, amino acids, polyphenols – is closely tied to stable growing conditions."

Christian Aid also warns the biggest impact is on smallholder farmers and tea producers in the countries where tea is grown who are being hit by climate change, along with issues including the rising price of fertiliser and fuel as a result of the war in Iran.

The charity is calling for action to support farmers, including developing more resilient tea plants, improving irrigation and planting shade trees to protect the bushes, as well as fair pricing, funding for producers to put in measures to help them adapt to climate change and protections for workers.

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.”