Protected and productive: How greenhouses should deliver UK food security

Societal Impact Statement The United Kingdom produces less than 20% of its fruit and ~50% of its vegetables, leaving it highly import dependent and vulnerable to supply chain disruptions. Our study maps 2085 ha of existing greenhouses, with over 70% being more than 40 years old, and identifies where modern infrastructure could expand production. Achieving 50% self‐sufficiency in greenhouse‐grown food by 2050 would require a fourfold increase and £14.1 billion investment, with a 3–7‐year return via import savings. Expansion would secure year‐round supply, reduce waste and create a resilient, climate‐ready food system. The evidence is clear: Strategic investment in greenhouses is essential for UK food security. Summary Greenhouses offer stable, year‐round fruit and vegetable production using minimal land. However, the United Kingdom currently produces less than 20% of its fruit and only ~50% of its vegetables, leaving it highly import dependent. This study maps the current distribution of greenhouses in the United Kingdom and estimates the spatial and economic requirements for reducing reliance on imports through the expansion of modern infrastructure. Spatial suitability modelling and economic analysis were combined to assess land availability, capital investment needs and return potential for scaling domestic greenhouse production. Of the 2085 ha of greenhouse space in Britain, over 70% is more than 40 years old. Achieving 100% self‐sufficiency in greenhouse‐grown fruit and vegetables would require 18,766 ha of modern infrastructure, a ninefold increase, costing around £26.6 billion. Meeting 50% self‐sufficiency would require a fourfold increase and £14.1 billion, with an estimated 3–7‐year return on investment via import savings. The south and east of England are most suitable for expansion, though production is viable UK‐wide with energy innovations and business co‐location. To improve food system resilience, greenhouses must be recognised as essential infrastructure. Achieving 50% self‐sufficiency in greenhouse‐grown food by 2050 is both attainable and strategically important. Without coordinated investment, the United Kingdom risks continued import dependence, food waste, and a fragile supply chain.