By Eric J. Smith
The use of wood waste in the landscape is often neglected for many reasons including no capacity to burn, aesthetic disadvantage or limited uses other than dumping. However, Hugelkultur is a method used for many years that can solve these problems and provide both long and short term benefits.
Hugelkultur in simple terms refers to raised garden beds on a base made with wood waste such as limbs, trunks, bark, chips and offcuts. These raised beds serve many purposes including water storage within the landscape, soil management, long term soil creation as well as creating habitat for beneficial insects and bacteria.
Beyond these typical benefits Hugelkultur mounds can act as weather barriers for smaller plants, and animals, increase growing area for shrubs, herbs, berries and vegetables, provide nutrients to growing plants and can also act as a carbon sink.
Building a Hugelkultur mound
The first step in building a mound is to removed the grass sods in the area it will be established. These sods will be placed on top of the wood pile before adding top soil.
A typical hugelkultur mound will be around 1 to 2 meters wide at the base with a similar to width height ratio. Logs and any sort of (untreated) wood and timber debris are piled up in a tight pile.
Add woodchips, bark and finer debris between the gaps of the wood debris and on top of this pile.
Add the grass sods upside down on the top of the pile – don’t worry if its not enough to cover the whole pile.
Add top soil, compost, straw, manure and other growing media – Visit http://www.permasoil.com.au for information on various soil creation methods used in Permaculture. Leave pile to settle for a week or 2 before planting out.
I recommend searching images on Google for Hugelkultur to see how the mounds are constructed.
A well constructed Hugelkultur mound will gradually reduce in size over the years as the wood and debris begin to rot. After around 20 years the pile will have fully broken down and will have left a rich soil such as you would find on the floor of a dense forest that has accumulated biomass in the form of fallen trees, limbs and other debris over a long period of time.
Typical plants grown on this pile will include Berry fruits, Evergreen and Perennial Herbs and Annuals.