How To Build A Swale When You’ve Got No Soil

In 1956 someone built a path.  Not a lot of thought needed to go into the path. People trod this path every day back and forth people as they walked to the letterbox, to friends houses, to school, to uni, to work, to orchestra, to the buses, to the city, to the beach, and sometimes to the rest of the world.

But the path had a dark side. It also worked very well to harvest water and direct it straight to the house.  fix-the-water-flowSo, finally, we built a new path that is happily compacted and maintained by the foot-traffic and channels water away from the house.

We then turned the old path into a garden. The biggest challenge was we had no soil and the existing path was compacted, rocky and dry. The garden beds either side worked well in our humid climate to support mediteranean plants such as rosemary, lavender and the chilli tree. Other plants such as the medicinal Aloe, common mint, Kaffir Lime, Grape and Fig have managed living in the rock dry soil.

Because carting soil from the other gardens would be heavy work and damage the food forest, we had to use our knowledge about how to build soil.  We’ve been building soil for the last 20 years. Soil needs 5 components: air (remove the compaction and use only stepping stones and keyholes), water, (catch and store so it can perculate through), minerals (sub-soil has plenty of these), organic matter (bring in the fibrous waste) and micro-organisms (build habitat and seed them in there when the conditions are ready.

So, without any soil on hand, we designed and built a new path to direct water away and a small swale that become a top contour path and a berm that will become a water holding bog garden. The design now:

  1. collects and stores water for the plants and
  2. redirect water away from the house foundations
The easy solution might have been to get in a load of soil. But by using hugelkulture and our no-dig technique for slopes we used up our collection commercial waste -1. cardboard waste (demonstrating how to be careful not to repel water) and 2. grass clippings (in a way that does not to encourage weed seeds) 3. some off cuts from a friends building site and 4. a heap of selected weeds.