Hügelkultur

Hügelkultur is a composting process employing raised beds constructed from decaying wood debris and other compostable biomass plant materials. The process helps to improve soil fertility, water retention, and soil warming, thus benefiting plants grown on or near such mounds.

Hügelkultur replicates the natural process of decomposition that occurs on forest floors. Trees that fall in a forest often become nurse logs decaying and providing ecological facilitation to seedlings. As the wood decays, its porosity increases allowing it to store water "like a sponge". The water is slowly released back into the environment, benefiting nearby plants.

Mounded hügelkultur beds are ideal for areas where the underlying soil is of poor quality or compacted. They tend to be easier to maintain due to their relative height above the ground. The beds are usually about 3 feet (0.91 m) by 6 feet (1.8 m) in area and about 3 feet (0.91 m) high.

Hügelkultur is a German word meaning mound culture or hill culture. It was practiced in German and Eastern European societies for hundreds of years, before being further developed by Sepp Holzer, an Austrian permaculture expert. In addition, recent permaculture voices such as Paul Wheaton and Geoff Lawton advocate strongly for Hügelkultur beds as a perfect permaculture design.

In its basic form, mounds are constructed by piling logs, branches, plant waste, compost and additional soil directly on the ground. The pile has the form of a pyramid, and is about 1.5 m high. The sides of the two slopes both have a grade of between 65 and 80 degrees.

When positioned on sloped terrain, the beds need to be put at an angle to the hillside (rather than having them parallel to it). This makes sure the beds do not receive unequal amounts of water. In most cases, it's also useful to have the beds positioned against the prevailing wind direction.

The raised bed can form light-duty swales, circles and mazes. Mounds may also be made from alternating layers of wood, sod, compost, straw, and soil. Although their construction is straightforward, planning is necessary to prevent steep slopes that would result in erosion.

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Wikipedia