Keyhole Gardening: a Drought-Tolerant, Compost-Style, Sustainable Concept
The key hole garden concept is quite simple. A circular planting bed (with a “keyhole” to allow access to the center) is constructed with bricks, stone, gabion-style walls, or even aluminum siding. In the center of the keyhole is a circular compost bin in which kitchen scraps and household “gray water” are poured.
Layers of soil inside the circular walls slope slightly outward to encourage positive drainage away from the central compost bin. As kitchen and garden waste breaks down and gray water is added, a natural “compost tea” soaks into the surrounding soil providing nutrients to plants growing within the circular wall. More information and instructions at the link.