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Urban cultivating vegetables, flowers, fodder on trays that hang from the outside walls of one's house, Up to 8 m2 irrigated area automatically watered with waste water.

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Green Walls
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Prototype Fivefold reduction of cost To be used in a modern economy Nutricion Comfort Urban

Growing vegetables, flowers or fodder for husbandry in urban and arid conditions can make good use of the space available along the outdoor walls of someone's house. If in total 6 meters wall lengthwise would be used for 4 sets trays above each other, about 8 square meter would become available for this purpose.
Collected waste water (quantity guess is 5 persons x 40 liters each = 200 liters daily available) could be used for watering the plants.
Techniques could be applied as used in modern greenhouse agriculture, as done by the Israeli in the Negev dessert. The general setup has to make a small scale use of these greenhouse techniques possible.
The work regarding controlling humidity, heat, nutrients, plant diseases and damage by insects can be done by people who stay home most of the time.

Trays, that hang from a wall holds pots with plants or seedlings in plastic bags. The trays are made out of bits of wood and sheet metal, about 30 cm wide and one meter long. The trays hang from the wall, using space as available, next to and above each other. Such trays are covered with plastic and can hold a thin layer of water. Waste water from the house is pumped up from a tank to the tray that is positioned highest. From there it runs slowly from one tray to an other, placed a little lower. See ClothPump for details on the pumping system
To protect and control temperture and humidity the set of trays is covered by transparent plastic, hanging down in front of the trays. This plastic can be easily removed to give access to the plants.

Planned progress

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Links related to Urban Agriculture

What other people say...

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by Hans Baarslag - Sun Nov 02 (2003)
In my language I would call it muurfilter voor grijswater or translated grey water wallfilter.or grey water graffiti.AS slogan Use your walls the green way I think it is also feasable to fill the top tank by bucket so no electricity is needed for the pump

by Hans Baarslag - Sun Dec 04 (2005)
I think the simplest way for feeding the grey water into the green wall is by buckets .These buckets can fill a storage tank from which the grey water is slowly leaked to the top tray. greeting Hans B

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