A green wall is a wall partially or completely covered with vegetation that includes an artificial growth medium instead of soil and an irrigation system with drainage.
Depending on the size or orientation toward the sun, certain types will be recommended for a perennial green.
One of the primary benefits to buildings with green walls is added energy efficiency, due mainly to plant evapo-transpiration. The added aesthetic value of green walls not only increases people's appreciation of the space, which improves their well being, but can also increase property values. Green walls also absorb greenhouse gases and pollutants.