04:32The Food ChainCan you feed a city from its rooftops?BBC World Service Duration: 30 minutes Thu 22nd Jun 2023, 04:32 on BBC World Service West and Central AfricaAvailable for over a yearListen nowWe meet the people farming on top of buildings. Show more GenresFactualFood & DrinkFormatsMagazines & ReviewsBrandThe Food Chain Source: BBC Online