RHS fears non-native fungi could alter microbiology of soil when grown in gardens or disposed of in compost heaps

A boom in the popularity of mushroom-growing at home could lead to a biodiversity disaster, UK garden experts have warned.

There has been a rise in the number of people growing mushrooms in their gardens, and this year, the RHS Chelsea flower show’s plant of the year award included a mushroom – the tarragon oyster mushroom, thought to be found only in the British Isles – in its shortlist for the first time, despite it being a fungus, not a plant.

Party hopes to lure voters who want radical change and strong climate policies, rather than centrism

Labour will face a renewed attack from the Green party in key marginal seats at this general election, as the group known primarily for its climate stance tries to reach voters who want radical change rather than centrism.

In sharp contrast to all of the main parties, the Greens will make an unabashed argument for higher taxes, which they will say are needed to fund the NHS, education and other priorities, alongside their call much stronger action on the climate crisis.

Exclusive: Labour calls on firm to urgently test treatment works after dozens in south-east London experience vomiting and diarrhoea

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Steve Reed, Labour’s shadow environment secretary, has urged Thames Water to “get a grip” and test treatment works “urgently” after it emerged over the weekend that the company had tested the water at only one property.

Over the last two weeks, dozens of people in Beckenham, south-east London, have reported becoming unwell with diarrhoea and vomiting. The symptoms in most cases have lasted for an unusually long time – up to two weeks. They have also been severe, with multiple people hospitalised, including an eight-year-old boy.

Regulator understood to be looking at ‘recovery regime’ for Thames Water and others in sector

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Ofwat, the water regulator for England and Wales, is understood to be considering cutting fines for sewage-dumping water companies if they are facing financial pressures.

According to the Financial Times, which first reported the plan, the regulator intends to draw up a “recovery regime” for Thames Water, which is facing collapse or restructuring owing to its high debts, and others that find themselves in similar positions.

Exclusive: after cryptosporidium outbreak in Devon, residents in south-east London report stomach cramps and diarrhoea

Thames Water has sent samples of water for lab testing after dozens of people reported becoming unwell with stomach cramps, vomiting and diarrhoea in south-east London.

Earlier this month, unsafe drinking water led to more than 100 cases of a waterborne disease in Devon, with people asked to boil their water because of contamination fears.

Display at Chelsea flower show highlights work in UK and US to bring orchid habitats back to health

Scientists are racing against the clock to save the world’s orchids by discovering the soil fungi they need to thrive, breeding them and then, in a first for conservation, transplanting them into orchid habitats.

Among the showy blooms at Chelsea flower show this week was a moss-covered exhibit, sprouting from which were the types of rare, native flowers one does not normally see at horticultural exhibits.

Leadership now sees environment as core issue for voters and strong dividing line against the Tories

Labour is planning to make the climate a key focus for its election campaign, putting its net zero commitments “up in lights”, and drawing a clear link between the “chaos” of the Conservative government and the effects of the climate crisis.

Fears over the climate – exemplified by a sopping Rishi Sunak calling the general election in a downpour on the same day scientists warned about the increased likelihood of seemingly “never-ending” autumn and winter rain – will be tied strongly to what Labour will portray as a polluting and careless Tory vein of climate denial.

Speaking at the UK River Summit, Philip Duffy said officials do not want to reveal the true ‘embarrassing’ environmental picture

The head of the Environment Agency has admitted that freedom of information requests have been buried by the regulator because the truth about the environment in England is “embarrassing”.

Philip Duffy, the body’s chief executive, told an audience at the UK River Summit in Morden, south London, this week that his officials were “worried about revealing the true state of what is going on” with regards to the state of the environment.

Many hoped he would show global leadership – instead he pitched himself as ‘pragmatic’ and slowed the journey to net zero

Every time a UK government minister is asked about the climate crisis, the answer is the same. “We are the first major economy to halve emissions and have the most ambitious legally binding emissions targets in the world,” is the response, or a variation on those words.

It is true that since 1990 the UK has cut greenhouse gas emissions further and faster than any other major developed economy, while increasing the size of the economy. Emissions per capita are now lower than they have been since the mid-nineteenth century.

Final dividend hiked by 9% as MPs write to Ofwat boss urging him to deny water firms’ requests in price review process

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Severn Trent has increased its payout to shareholders despite being responsible for 60,000 sewage spills last year.

Severn hiked its final dividend by 9% to 70.1p a share after pre-tax profits swelled almost 20% to £201.3m in the year to the end of March.

First-time exhibitor Ula Maria scoops best in show for garden designed for muscular dystrophy charity

A garden demonstrating the joys of forest bathing has won best in show at the Chelsea flower show.

Designed by the first-time exhibitor Ula Maria, the garden was inspired by the ancient Japanese practice of shinrin-yoku, which means being calm and quiet among trees, breathing deeply and observing nature.

Design created with no concrete and completely sustainable materials is first to win new environmental prize

A garden built with “humble” terracotta made into 3D-printed bricks has won the first green medal at Chelsea flower show for being the most environmentally sustainable design.

This year’s show, held in the Royal hospital gardens in south-west London, has a strong environmental theme. At the press day on Monday, Dame Judi Dench was presented with a seedling taken from the Sycamore Gap tree unlawfully felled in Northumberland.

More than 216,000 fish died in 2022-2023, when England recorded a 54% increase in sewage spills

Mass deaths of fish in England’s rivers have increased almost tenfold since 2020, with fears sewage pollution is exterminating life in the country’s waterways.

Environment Agency (EA) data from the past four years shows an alarming rise in the number of fish deaths linked to sewage pollution, with figures escalating from 26,690 in 2020-2021 to 216,135 in 2023-2024.

As the prestige flower event begins, horticulturalists are shown how a waterlogged patch can help counter climate crisis

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.