Here is an article that claims that the carbon footprint of urban agriculture is six times larger than conventional produce. https://phys.org/news/2024-01-food-urban-agriculture-carbon-footprint.html It includes small home gardens in urban agriculture and claims that the main contributor to the large footprint is the amount of infrastructure that has a limited useful lifetime. I can see this to be true for the vertical gardens that are being built in urban areas, but I can't believe that it is true for typical backyard gardens. Most home gardens don't have elaborate structures, except for the few that include greenhouses. I think that many urban gardeners, myself included, try to use scrap material as much as possible in building raised beds and other infrastucture.