Hugel w one layer of dirt

Howdy
I'm thinking of making a hugel with just the sod-flipped-over layer on top of wood + covered with grass mulch. Could this work? Looking to lower the work level since it'll be a huuuuge area and I'm doing it by hand. Don't really care about height/it melting, it's just for wildflowers, soil health and weed control.

To me, soil plays an important part of a hugelkulture bed.

Soil is usually placed among the wood to help with the process.

If you do not have soil to place around the wood, then maybe there are things that could be substituted like leaves, coffee grounds, and veggie scraps.

I might be mistaken though I feel the reason hugelkulture beds are so tall is part of the process.  As the wood decays the tallness gets shorter.

If I am mistaken then I hope someone will explain why a hugelkulture bed needs soil amoung the wood.

There's a fair bit of posting on Permies about hugel mounds becoming rodent colony dens. The general consensus seems to be if you leave gaps around the wood, something will move in to use those gaps. If you're filling in each layer with soil, there's fewer and smaller gaps.

While you COULD do a hugle that way, don't count on being able to plant anything on it for a few years until things start to break down into some semblance of growing substrate. Adding soil is important to give plants something to root in, and flipped sod is not enough. And as someone else mentioned, without soil filling the gaps you invite critters to move in.

The big air gaps also create space that roots can't do anything useful with until it collapses (ever heard of an air pruning box?) vs being able to weave around everything and dig into the cracks and crevices of the wood.

Plus the water (and other nutrients) held onto by the wood can't be transferred to the surrounding soil (and its microbes) like you want it to because of the air gaps.

I've done some mounds like this. They usually end up with alot of grass etc. growing back out of the sod that needs to be covered with more mulch later in the season. In the shade of the forest, they do ok to grow raspberries after a couple years, once the wood starts breaking down. It also seems to be a good way to quickly cover a pile of fallen trees to prevent fire, as they stay pretty damp afterwards. The mounds I've done this way in the sun stay dry/need watered, but will usually grow legumes well enough in my climate in the first season. Lupines have done well, relatively. It seems to be better where I am to have the wood atleast partially below the surface, which requires a bit of digging but offers a bit of soil to later fill in some voids, speeding things up.  

Hi Almond,

If the Hugel bed doesn't work out, you could always use the sod to make a turf stack. It is essentially just layers of sod stacked in alternating fashion (Grass up, grass down, grass up, etc.), and left to compost for about 2 years. Ensure none of the layers of grass are setting seed as well. The top layer should be grass down and it should be concave to some degree to allow rainwater to infiltrate the pile. Set off to the side and allow it to break down fully! I have not tried it personally but wanted to give you the option as the resulting soil is supposedly superbly structured. In fact, it is referred to as "loam" in a generalist definition, no doubt the decomposition of all those fibrous root systems aids in creating structure.

Hope this helps,
Eric S.

Hey Eric, great idea. I'm currently trying that, thanks!!

You could also listen to Paul's latest podcast with Samantha, who won a permaculture consultation with Paul from a previous kickstarter. Paul visits Samantha's new place and they discuss future plans, including plans to grow a million calories on dirt, fertility and hugelkultur beds.

https://permies.com/wiki/223738/Podcast-Samantha-Consultation