In 2007, for the first time in human history, the majority of the world’s population were living in cities. That point was just a marker as part of an upward trend: the urban population is predicted to grow from this point forward with very little clue as to when that growth will slow. As a result, our cities will become denser, affording the population less horizontal space for private, as well as public use.
In a City of 3 Million-esque attempt to replace the potential green space that buildings are now occupying, planted roofs have become a more viable option. These spaces have many positive ecological and sustainable effects, but tend not to be able to be occupied, particularly visible, or interactive. The importance of plant presence in our living space has just started being studied: plants have been shown to reduce stress, lower blood pressure, increase attention span, reduce aggressive tendencies, etc. With a loss of yard space, individuals are losing opportunities such as gardening or even lawn mowing to interact with greenery. Vertical surfaces now need to fill a function in cities that horizontal surfaces no longer have the opportunity to do.
Current hydroponic systems have been developed in part as a reaction to the space limitations of an urban environment. Dirt, a commodity in most cities, is not required for plant development. Only water, a substance in which cities provide an infrastructure for delivery and removal, imbibed with nutrients is needed for growth. The system allows the plants to be grown very densely and vertically, offering the opportunity for mass production in a small area. This strategy has been applied on a household and production scale. Because the system is so adaptable, hydroponic systems have taken many forms and locations. In Japan, a Subway shop opened that provides fresh “picked” hydroponic lettuce. The NFT Spiral System uses a unique form to gravity feed the plants in an efficient manner. A system that I developed last semester acts as a flexible curtain and makes use of window day lighting and efficient use of vertical space.
The vertical nature of the hydroponic system continues to be utilized by city dwellers, usually filling up available volumes. It is not a far to jump to imagine these surfaces integrating hydroponics into wall systems or second skins that would have the possibility to provide shading, cool bio-climates, and potentially produce as well.