Here how i made my vertical vegetable garden, starting from used big water bottles as planters. An automatic watering system keep the right moisture, collecting water in excess, using power from pv panels and a little wind turbine (vawt)
Step 1: 3d Project
The green wall is composed by 72 water bottles cut and placed upside-down on a wooden shelf.
Two independent water reservoir are present: the main is placed on the side of the building and composed by eight 200 liters barrels linked together, for collecting rain water. The second one is composed by three plastic "new jersey" street barriers, that can contain 80 - 100 liters each, placed under the shelf.
The circulating system is composed by two 12v pumps, powered by a hybrid power system, a vawt turbine in conjunction with two 10w pv panels.
Energy is stored in a 12v car battery via charge controller and a timer regulate the watering cycle (at this moment the set up is 1 min at 7 am and 1 minute at 7 pm.
Water is pumped from second reservoir to the top of the shelf, into a PVC pipe ( Dia 4 cm) where i drilled eighteen 3 mm holes (one for each planter of the first row). After moisten the first row, water goes down to the rows below until go back to the starting tank.
With hand activated valve i can refill the second reservoir with rain water from blue barrels.