A Hügelkultur Adventure

This last month I had the "joy" of putting in two new beds to make room for more flowers this next spring. Both beds had to be cut out of the grass and both had soil that has suffered from lack of care over the years. I needed to do something to replace the soil taken out with the sod layer and also help the nutrient in the soil. I turned to my handy dandy friend Google to see what he would suggest for me.

As I searched I came across a new word, "Hügelkultur". It's a German word that translates to mound culture. Though the word is German, mound culture is something that has been around for thousands of years. You could call it the first use of a compost mound.

So, what is hügelkultur? The quick explanation is the process of using rotting wood to feed and water your plants. How does it do that? Wood logs are placed at the base and then twigs are piled on top followed by mulch, compost and soil. Traditionally these mounds are built up to 3 or 4 feet. The rotting wood at the center of the mound holds onto water and plant roots are able to leech off of it. The rotting wood and compost help to feed the plant roots as things continue to decompose.

This idea of mound culture intrigued me. It sounded very similar to what people refer to as lasagna gardening but with larger logs at the bottom and of course there is the fact that it's a mound. I continued researching and came across a few people that had applied this idea of mound culture to their raised beds. After pondering the idea for a little bit I decided I could adjust this concept to my in-ground bed. We had just chopped down a plum tree and I had some good sized logs I could use.

Armed with my new found knowledge I grabbed my shovel and went to work. I removed the sod layer and dug down about a foot.

Once I had removed enough dirt I placed branches and twigs along the bottom. The above picture is from the smaller bed where I used smaller branches. The second bed received the larger logs. I wanted to see if there would be a difference in the out come of the plants if I used more small branches vs a smaller amount of larger logs.

After enough wood and sticks had been placed in the hole I then raked up all our leaves and stuffed them in between the wood.

My kids had a fun time helping me stomp on the wood and leaves to really pack them in. Between the wood and the leaves my 12" hole was almost filled. Once the leaves were packed in I gave everything a good soak with the hose. Wet wood will decompose faster and soaking everything helps to kick start decomposition.

After the leaf layer and soaking came a layer of mulch and rabbit droppings (seriously the best animal fertilizer ever!) I then topped it with a couple inches of soil, added a few bricks around the edges and the bed was done!

The only hesitation I had with taking this route was the amount of nitrogen that wood uses to decompose. While wood does add a good amount of nitrogen to the soil after it's broken down, the process of breaking it down can use quite a bit. This could result in less nitrogen for the plants. The addition of the compost and rabbit droppings will help to combat the loss of nitrogen due to the wood decomposing.

Using this method can also help with weed control in garden beds. The wood at the base of the bed will act like a sponge and soak up water. The plants will then send out roots to find that water and leach it from the wood sponge. This actually helps to promote a healthier root system because the root system will be spread beyond just the surface level. Having all the roots at surface level can easily happen when plants are watered to often and to shallowly. With roots being able to reach the deeper water source the top level of the soil can be allowed to dry out a little more. Thus when new weed seeds try to sprout in the top layer it will be harder because of the diminished amount of water close to the surface.

This method would also be a great way to fill raised garden beds without spending an arm and a leg on raised bed soil. If done properly the first 12-18" of a raised bed could be filled with logs and composting product. Most plants only need 8-12" of soil to be healthy and happy.

The garden beds are now all covered with snow but I'm excited to see the effect this method has on the plants next year. Stay tuned to find out how they do. Until then Happy Gardening!