A tale of two cities: rooftop gardening in Hong Kong and Beijing

American documentary series The Perennial Plate is all about sustainable eating.

For its third season, chef Daniel Klein and producer Mirra Fine travel the world, looking for alternative ways of farming and eating. Their short videos are a treat, giving us a peek into our increasingly interconnected food system.

Here they take to the rooftops of two of the world's most populated cities, showing it's possible to indulge our pastoral fantasies smack in the middle of town.

And for those of you interested in the state of food in China, here's a story of one woman in Kunming bringing healthy and organic food to the city.