Hugelkultur is the most talked about concept in the permaculuture world. The idea with hugelkultur is that you mound or bury logs in compost and plant in it. Proponents contend that the logs break down and become open fungal pathways to store water and nutrients.
Kelly suggested we take an unused raised bed in our front yard and try an at-grade hugelkultur experiment (mounding in our dry climate seems like a bad idea, especially given our current drought). I balked at the amount of digging that would be involved. Kelly suggested that we should try it since we had little to lose and we’re supposed to be experimenting with garden ideas for the sake of our readers. I, again, thought about all the digging and the excess soil that would have to be carried down the staircase.
Then I had a change of heart. We should be experimenting, I thought. And we have a pile of wood.
But, like a gardening version of Hamlet, I started waffling again. I decided to post the hugelkultur question to the Garden Professor’s Facebook page. One of those horticulture professors, Linda Chalker-Scott is someone who I seek out when writing a magazine article. A civil discussion ensued on that Facebook page, proving that Facebook is good for something other than angry political screeds and cat videos. A summary of some of the points made:
- There is no peer reviewed research on hugelkultur.
- The concept seems to date back only to 2007 or so, most likely to Sepp Holzer.
- Chalker-Scott suggested that you could get the same benefits with surface mulch with a lot less effort. See a previous Root Simple blog post for the reasons why mulch does many of the same things as hugelkultur.
- Someone pointed out that subsidence in a hugelkultur bed might be bad for trees, though many use hugelkultur just for vegetables.
- I pointed out that nature mulches but does not hugelkultur (except maybe in the case of floods).
- Relieved that I would not need to dig, I chimed in that I thought that hugelkultur would rob soil of nitrogen as the carbon material broke down.
- A hugelkultur supporter countered that large logs would not rob soil of nitrogen due to the surface to area ratio.
- The conversation concluded with a back and forth on mulch vs. hugelkultur and the benefits of hugelkultur as a method to break up compacted soil. Again, the issue was that mulch takes less effort.
What’s needed is a field trial to answer a few questions. Would surface mulch alone work just as well? What is the effect of mounding? Would at-grade hugelkultur work better in dry climates? Does hugelkultur save water? Since I’m lazy and especially don’t like big dig projects I’ve decided to forgo a hugelkultur bed. But I also don’t want to completely dismiss the idea.
What do you think?