Definition: An enhanced living fence composed of three rows of shrubs and trees planted around the perimeter of the Forest Garden. A green wall is designed to protect the land and crops from strong winds, unwanted intruders, and livestock, while at the same time providing numerous secondary benefits.
Green Walls in the Forest Garden:
While a living fence around the perimeter of the field can provide adequate protection from animals, farmers who struggle with strong winds and larger intruders often choose to fortify their living fence by turning it into a green wall.
Instead of a single or double row of trees and shrubs, a green wall consists of 3 rows that create a fortified barrier capable of keeping out intruders of all sizes. In fact, a Forest Garden farmer in Kédougou, Senegal designed a green wall that was able to withstand multiple charges from a hippopotamus!
In addition to fortified protection, a green wall can also serve many additional purposes. Farmers often choose to plant tall, fast-growing trees like Grevillea robusta on the inner row of their green wall that will protect the field from strong winds. Farmers also choose to include nitrogen-fixing species to revitalize the soils or choose other species that provide sustainable sources of useful products like timber, fodder, food, and fuelwood.