The Green Party of England and Wales has been described by a former party staffer as having been a "watermelon" group for at least a decade. This term refers to individuals or organizations that appear environmentally focused on the surface but have socialist ideals at their core. Russell Warfield, author of The Green Socialist: Zack Polanski and the Battle for Britain’s Future, argues that this evolution into a more socialist-oriented party is not recent but has been a 50-year development, making the Greens the main electoral force on the British left. Warfield traces the party’s core positions back to the early 1970s, suggesting that its current identity is the result of long-term ideological shifts. Zack Polanski, the current leader of the Green Party, has faced criticism from within the party, with a senior Green source calling his rise to leadership a "hostile takeover" during the 2025 contest against co-runners Adrian Ramsay and Ellie Chowns. However, Warfield disputes this, citing Polanski's 85% victory in the leadership race as evidence of widespread support. Caroline Lucas, the Greens' first MP and a former party leader, has urged Polanski to focus more on environmental issues, which have historically been the party's main appeal. Warfield highlights that the Green Party's strong association with environmental action is a key reason for its political relevance. According to YouGov polling, 34% of voters trust the Greens more than any other party on environmental matters, the highest level of trust for any party on any issue. He argues that the party's shift toward a broader political message, including social and economic policies, is a natural evolution, built on the foundations laid by previous leaders. Despite its environmental focus, the Green Party has complex origins. Warfield notes that some of its early figures had rightwing affiliations. For example, Teddy Goldsmith, an environmentalist from a prominent Tory family, played a key role in shaping the party’s ideological foundations. However, Polanski’s tenure has not been without controversy. He faced criticism for comments on the police response to the Golders Green attack, which the Met commissioner called "inaccurate and misinformed." Polanski was also involved in a false claim about being a British Red Cross spokesperson and shared a photo of a man wearing a T-shirt with a guillotine and the phrase "we're only making plans for Nigel," a reference to Nigel Farage. YouGov polling shows that Polanski’s approval rating has dropped since becoming leader, and Green voting intention has fallen from 21% to 11% in recent months. Warfield acknowledges that some of Polanski’s actions, such as the guillotine image, were missteps, but he argues against limiting Polanski’s social media engagement, emphasizing the need to maintain his political authenticity. On 8 October, Polanski will contest the Holborn and St Pancras byelection after Keir Starmer announced his decision to vacate the seat. Warfield believes Polanski has a chance to win, suggesting that a Green candidate could exert pressure on the Labour Party from its left.