Deep Mulch Gardening: Building a Habitat for a Whole-Soil Ecosystem

According to the literature, hügelkultur can remain fertile for up to 30 years without adding new materials. However, it can be difficult to plant into the logs and branches. We call our latest experiment a hügel mulch. It is a base of logs and branches covered with a wood chip sheet mulch that should give us many years of growing without any labor except planting and harvesting.

At the Living Systems Institute we work with the theory that nature maintains a habitat for a whole soil ecosystem that retains nutrients. By “whole soil ecosystem” we mean a complete set of organisms that cycle nutrients through complete growth, decay and regrowth cycles. I have been working with the concept over ten years now and I know I can grow more vegetable with substantially less work using a deep mulch system than with any of the other gardening technique that involves turning the soil. In my experience maintaining a habitat for that whole soil ecosystem is why it works.

Experimenting with Deep Mulch Systems

I started the experiment in 2004 using the permaculture technique called sheet mulching.[1] By 2011 our gardening teams were incorporating ideas from a technique called hügelkultur.[2] One third of our 2011 experimental sheet mulch garden was built with varying sizes of branches, sticks and wood chips twelve inches deep, then covered with an inch of horse manure. The section using hay has been renewed annually, the section using only wood chips will need to be renewed this fall. We planted the section built with branches for the 4th year in 2014 and it shows no sign of slowing down.