I found a most enlightning post about it on Landscape+Urbanism from Jason King. Seemingly lots of gizmo techniques about space environment producing crops some of the mentioned techniques and structures are very well suitable for small scale production as well!
A future problem of the urban environments is not only the large scale water consumpion but congestion as a result of the never ending supply of food as well. What if most of the inhabitants were able to grow their own vegetables. They would have a better quality of food and, added bonus, it would be cheaper in two ways: less transport and cheaper to make than buy. The only thing is; it takes time to grow it.
Nevertheless let's take a look at the futuristic and cunning structures, architecture and most of all conceptual projects. Below a selection of them. For the complete article go here.
picture above: The Plantagon project is one of a raft of recent projects designed to make urban environments more sustainable in the long term. For example, pictured here is a project called DragonFly. The 600-meter-high (almost 2,000-foot) vertical greenhouse is shaped like the wings of a dragonfly and was created by the Belgian designer Vincent Callebaut. It is designed to house livestock and a wide range of crops.
(above: City Farming in a Plantagon Greenhouse. With its largest glasshouse model estimated to cost about €70 million ($104 million), the costs of such projects are huge — but so are the environmental changes the world will face in the years to come. The stark facts of global warming, combined with population growth, speak for themselves (source: cityfarmer.info)
Looking into the economics and politics of rising food prices and theories about impending food shortages led us to create the “food farm” to test peoples sensitivity to the issue. We wanted to develop something initially that would supplement the nutritional needs of a family living in high rise accommodation, without drawing electricity or gas (source: cityfarmer.info)
And now: let's go and try to develop something alike for my own roof, and see if I can grow my own crops without all the high-tech installations. Vegetables instead of a green sedum roof: Vegitecture?!