Food production doesn鈥檛 only happen in fields or factories. Nearly 1 billion people worldwide produce food in cities. In Kenya's Kibera slum, the largest in Africa, farmers are growing seedlings of indigenous vegetables and selling them to rural farmers. At Bell Book & Candle restaurant in New York, customers are served rosemary, cherry tomatoes, romaine, and other produce grown from the restaurant鈥檚 aeroponic rooftop garden.
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A rooftop garden on a building in Durban, South Africa. In Johannesburg a nonprofit group is using rooftop gardens to teach farming skills to urban youths and to inform them about the effects of global warming.