India, Oct. 15 -- Indian cities grow hotter by the year. Anyone commuting between May and July knows the physical toll, as heat radiates from asphalt and concrete. As built-up areas expand, mature trees disappear or retreat into ever smaller, fragmented patches, leaving residents with little relief from scorching pavements and recurring heat alerts. Scattered ornamental shrubs, planted in fenced traffic islands and coated year-round in road dust and vehicle emissions, do little to cool surrounding neighbourhoods or provide shade for pedestrians.

To deal with this crisis in Indian cities, the Union Ministry of Environment, Forest and Climate Change launched the Nagar Van Yojana in 2020. Financed through the National CAMPA Fund (Compensato...