Hybrid hugelkultur

From what I can understand, classical hugelkultur consists of piling up logs and branches, filling over with topsoil and planting on top.  The decaying wood adds fertility and heat to the heap, which is good for the plants growing above, and it also provides some heat to the heap.  I'd never heard of hugelkultur until I read about it on Craving Fresh, I thought at the time that it was an interesting concept, especially when we have such cold winters here, but I wasn't sure what to do with it.  Then someone from our permaculture group sent around another link with some great pictures and I was even more interested, but still not sure what to do.  The problem is that we lack topsoil as it is, and I wasn't going to buy any.  We do have plenty of logs that are too big for the mulcher though, so I was still interested.

Then we went to a permaculture techniques day with our permaculture group, and looked at some hugelkultur and swales at the Bottle Tree Hill Organics farm.   Swales are kind of like contour banks across slopes, consisting of a trench uphill and a mound downhill, used to hold water on the surface of a slope for longer, to allow it to soak into the mound of dirt and to direct water towards dams etc (diagram and info here).  We have plenty of slopes, erosion, dry spots, so we could definitely see the need for swales of some kind, or maybe more like Peter Andrews style contour banks to direct water and fertility (a contour bank doesn't have so much of a trench on the uphill side).  Even though we have the little tractor, we weren't sure that it was up to the task of digging trenches and building mounds on a large scale.

We decided to build more of a hybrid hugelkultur-swale to help with the rehabilitation of the particularly eroded area on our property and as somewhere to plant any extra seedlings!  The hybrid hugelkutur consists of a pile of logs and branches on the slope above the drain, which has virtually no top soil left.  On top of that, I put 3 wheelbarrow loads of cow manure and then a big load of hay (that our ungrateful lovely cattle didn't finish from their last round bale).  The logs are positioned to stablise the heap and prevent from washing down the slope in the next heavy rain.

Our hybrid hugelkutur-swale-contour thingy

The next step was to plant out seedlings and seeds on the mulch.  My aim here was to grow anything that would produce green material to add to the fertility of the soil in the hugelkultur, so I added any extra seedlings or divisions that needed a home, including parsley, dill, geraniums, comfrey, arrowroot, marigolds and cherry tomatoes.  The main thing was that all the plants were safe for the cattle to eat if they did escape the safety of the electric fencing around the eroded area.

Unfortunately the first part of this summer was not as wet as initially forecast, and the occasional 10 mm of rain here and there, interspersed with impossibly hot days, was not enough to sustain all the plants, particularly with no shade over the mound, and some plants didn't make it.  I tried to be blase about the hugelkultur, but I did end up taking water buckets up there and giving it a few drinks, just to keep something going (if only the microbes and the worms).  Now finally it has rained, and I can see that some of the plants are doing well.  Its quite fun having it as an overflow garden.  It doesn't matter what survives and what doesn't.  It doesn't matter if I don't ever harvest anything, and it doesn't matter if its full of weeds, as long as something is growing up there and starting to establish some top soil on the slope.

Already we can see sediment and organic matter accumulating on the slope above the hugelkultur, this is all fertility and potential soil that would have been washed away in the past.  Last year I did pile grass clippings on the area, but without the logs to stabilise the heap, it didn't last long.  We also learnt that its better to spread out a small thick pile of grass rather than spread more thinly over a larger area.

Since building the first part of the hugelkutur we have continued to to extend it across the slope, with more logs, manure, grass clippings and hay as they become available.  I also put down some wet newspaper under one part of the pile because the pile of useful newspaper was getting too big.  And when we spent some time weeding the garden, the whole lot when onto the hugelkultur as the compost was full.  We hope this will be the beginning of building top soil and eventually a stable grass cover in this area.

If you are wondering how this would work in a smaller garden, see the post on Craving Fresh.

Sometimes it takes a bit of thinking to work out how a permaculture concept can work on your property, at your scale and with your resources, but when you come up with something that works, its a great feeling!  

Have you tried hugelkultur?  

Each month in 2013 I reviewed a principle from David Holmgren's Permaculture: Principles and Pathways beyond Sustainability:

Observe and Interact
Catch and Store Energy
Obtain a Yield
Apply Self-Regulation and Accept Feedback
Use and Value Renewable Resources
Produce no Waste
Design from Patterns to Details
Integrate, Rather than Segregate
Use Small and Slow Solutions
Use and Value Diversity
Use edges and value the marginal
Creatively Use and Respond to Change