HUGELKULTUR
A horticultural technique where a mound is constructed from decaying wood and other compostable biomass plant material, leaves and wood-chips, then planted as a raised bed. It is a centuries old way of preparing a garden bed.
The air pockets allow plant roots, water, and air easy access to deeper soil layers. Growth and microbial activity is significantly enhanced.
The method shown here demonstrates adding biomass 1 1/2 feet deep.
Another method that people use is to add biomass on top of the soil which also works well.
Orientation can create a warm side and a cool side of the bed.
We have had excellent results.