Under the leadership of Zack Polanski, the Green Party of England and Wales has experienced a surge in membership, with approximately 160,000 new individuals joining the party over the past year. Political analysts and observers have characterized a significant portion of this new base as 'watermelons'—a term used to describe members who are 'green on the outside and red on the inside.'

This factional shift suggests that many new members are drawn to the Green Party as a political home for socialist values, which they perceive as having been abandoned or vacated by the Labour Party. The trend is explored in the new book, 'The Green Socialist: Zack Polanski and the Battle for Britain’s Future,' which examines how Polanski’s leadership has aligned with this ideological transition. While the Green Party has traditionally focused on environmentalism, the influx of these members indicates a pivot toward a more explicitly left-wing economic platform. The Guardian reports that these members prioritize socialist policies alongside their climate goals, effectively merging the two movements. The rise of this group marks a notable change in the party's internal dynamics and broader political strategy, positioning the Greens as a potential alternative for voters seeking a more radical left-wing platform than what is currently offered by mainstream parties.