How to Hugelkultur

strawberries, 2 years on the hugel

As soon as I was introduced to the concept of hugelkultur, which roughly translated means "growing mound,  all I wanted to do was experiment with a hugelkultur mound in my yard.  Actually,  that's not true.  What I really wanted to do was build  hugelkultur beds EVERYWHERE.

My basic understanding of the technique was that it was a well constructed compost heap designed with a number of sustainable principles in mind such as water retention, soil building, increased planting area, and ease of harvest.  How amazing, right?  I mean who wouldn't want a hugelkultur bed in their backyard? I decided to build a mini bed on my parents small, urban lot in the pacific northwest in order to build soil and provide a place to grow a seasons worth of herbs and veggies.

My tiny mound boasts some healthy herbs!

Here are the basic steps to constructing your own hugelkultur mound.

Step 1:  Plan where your hugel mound will be  and where you can put materials during construction.   I remembered from my permaculture course that the best thing to do was to start small.  So I did.  The size of your hugelkultur will be dependent on what your site specific needs are.  It is not uncommon to build large mounds with machinery, but I had a very small space to work with and I was mostly just curious to see if it was a practice worth doing on a small scale.  So I dug a small, two foot wide, 5 foot long c-shaped... hole in my parents garden where I wanted the bed to go.  It was amazing how much soil came out of that hole.... I felt like it doubled once it was all dug up.

The chasm of  hugel and one of 3 mounds of soil I removed from it.

Step 2:  Collect materials - carbon and nitrogen.  The carbon component is basically wood in varying stages of decomposition.  I am sure one could write a book on how different types of trees at what size and which stage of decomposition effect the hugel process, but when you are starting out all you really need to know is this:

1. stay away from black walnut, black locust, cottonwood and any other plant with allelopathic properties.  They can inhibit the growth of other plants and are therefore not suitable for a "growing mound".
2. The "fresher" your wood is, the more carbon it contains and the more nitrogen it will need in order to decompose.
3. larger pieces of wood take longer to decompose and increase the life span of your mound.  

To get the nitrogen you can use grass clippings, good compost, manure, coffee grounds, and vitamin pee (yes, that is what you think it is).   

You will also need some good mulch and 1inch diameter branches (or larger, depending on how ambitious you are) to hold the mound in place.  

This represents all the carbon and about half the nitrogen 

Step 3:  Assembly   The larger, "fresh" rounds went in first, followed by a layer or two of aged firewood.  I packed smaller twigs and grass clippings into the empty spaces and continued to build the mound with smaller branches until was a whopping foot and a half above ground level.  Many beds are between 5 and 10 feet high and over a meter in width - I can't stress how important it is to make sure you have enough wood for your mound.  If you are having trouble guesstimating, form a small section beforehand to give yourself an idea of how much you will need for the whole project.  

Ready for planting!

Use the excavated soil to cover the mound, and be sure to compact the soil before covering the structure with a compost-rich soil amender.  Plant the mound, or broadcast seed generously before starting to "pin" the mound.  Lay some woody debris length wise on the mound and push the 1" diameter branches into the mound to hold them in place.  This will help to hold the shape and structure as the hugel bed begins to transform into nutrient rich soil.  The last step is to add a nice, thick layer of mulch.

  

After Words:  There are so many reasons to use hugelkulture mounds and for every location a different variation of this technique could be needed.  I planted this bed in October of 2013 and the pansies were beautiful all winter, we had a supply of bok choi well into the summer of 2014 (when it bolted), and the lavender, chives, parsley, oregeno, thyme and strawberries were still going strong last weekend.

There are plenty of great hugelkulture resources on the web, but here is the link to the video that inspired me to give it a try.

a couple weeks after installation - happy edible pansies and kale seedings!