Hugelkultur at the arctic circle

Hi, I live in the north of Sweden right at the arctic circle. I'm planning to set up some permaculture at my moms garden this summer. I'm especially interested in hugelkultur as we have lots of wood for this.

Our average annual temperature is around -5 degrees Celsius. Sounds cold, but in the summer the climate is great for growing, and my mom has been growing large amounts w/o permaculture for ~25 years.

I have a few questions:

Will hogelkultur work great in this cold climate?
I read somewhere that the wood breaks down in winter time, my guess is that this wont happen as much in this cold climate? Maybe I'll have to use solar heating and some pipes trough the beds to get it warm early in the spring, anyone tried something similar?

What size of the beds is recommended for colder climate? I'm thinking BIG, maybe close to 2m high?

And my final but most essential question; My speculation is that the colder climate will make the wood decompose at a slower rate. If this is true, would it be a good idea to put some manure in the beds as well? This manure will probably serve as a boost for the plants the first few years, but how will it effect the decomposing of the wood? Will it serve as a catalyst and have a long term positive effect?? My plan would be to put the manure together with the wood as the hugelkulture core.

I'll wait with great anticipation for all your experienced minds to work your magic!

Thanks! -Ivan

The wood breaking down slow does two things. Both are to your benefit.

Yes it will break down slower, but it will last longer abs release nutrients over a longer period of time.

As the wood breaks down slower a lot more of it is converted into soil humus rather that when it breaks down so fast and less humus is created. And we want as much humus in the soil as we can get.

And yes make them big, very big like you thought.

Thank you Jordan!

Why is it that more is converted into soil humus with a slower decomposition? And would manure make it decompose faster? I'm also considering to put some charcoal in the beds as I have heard that it stimulates microorganisms a lot?

I'll have to consider that my climate is a very cold one and I know for a fact that things takes a lot of time up here, do you think I'm aiming for the wrong target if I try to speed the process up by for example using manure?

Many thanks -Ivan

an exciting thing this project is ivan, cant wait to see it unfold

biochar (or charcoal is used a lot in tropical environments because it provides near permanant "housing" for bacteria nad the like, but it doesnt nessacarily feed the bacteria, just because its good in hot climtes doesnt mean its useless for you but its not the same nessecity (that beign said the more diversity the better so by all means through some charcoal in the bed)
it is popular because where it is always warm enough for decomp, decomp happens quickly and in so doing, there is little organic matter, or humus left in the soil, which results in the nutes and minerals being washed away or taken up by plants very quickly, with little to none of it being stored in the soil, in colder climates such as yours, the bacteria cannot fully decompose all the bits and piece of debris and leave behind a very diverse layer of organic matter called humus, which has immense capabilities to hold water and nutrients and make them available for plants, humus can buffer extremes in heat and cold as well as wet and dry and it is very important, imho the amount of humus that you have the capability to produce that far north is definately a great blessing

i think that by adding manure you are only diversifying the bed, and along with wood of all sizes, from twigs on up to whole trunks (or whatever you can get into with your resources) that diversity will give you the best results, i used manure in my beds and though i dotn think its nessacary in a hugelbed, i certainly see nothing wrong with it, and besides, even speeding it up, with your cold winters, its still gonna take a while to break down and you'll still get high quality humus as a result

My feeling on the manure is that it will help provide nutrients both for your plants, and the 'critters' that are decomposing your logs.
Any nutrients provided by the wood alone would be a very slow release...probably not enough.
I would be careful of packing the manure in there too tightly, as an important element of decomposition is oxygen. Most of the 'critters' cannot live without oxygen.

The manure, and its decomposition would also add some heat to your beds, thereby, probably extending your season.

In an arctic environment, the breakdown should be very slow with/without the manure.

As far as height is concerned, I think tall will work well for you. That far north, I would think beds running N/S would be most beneficial.
If the beds ran E/W, the northern slope would see no daylight until later in the season. Brrr.
A N/S orientation should give both sides good sun exposure in the long days of summer.

Good luck.

The other beneficial effect is surface the volume ratio. In theory, when air temperature goes above soil temperature (otherwise known as spring), the hugelbeet will warm up faster than flat ground, just as a raised bed. Check it with your thermometer... Id be interested in the sun trap shape... u-shaped with the opening south, maybe grow native nitrogen fixers on the cold north side.

What's your thoughts about using a solar air heating system to heat the beds in the spring? Anyone tried something like this?

well not being at all familiar with your particular climate i would say it has some positve affects as youll plan for but the negative effects may outweigh them in that it may cause the temperatures to stabilize between air and soil and when the air is cold it could quickly cool your bed, whereas leaving it closed could providea fair bit of insulation and allow some microbials and fungi to work the very center of the bed in deep winter if it is not installed, that being said i would certainly recommend a few dark stones, particularly on the southside to trap heat as the sun does shine on them and distribute it a bit better

however experimentation will definately be key for oyu as the long sunless winters may cause the rocks to actually cool te area more than warm it... something youll just have to look for and observe yourself, are there any dark rocks i nthe area for oyu to observe the plant life near them?

If you have the spring sunlight, that'd be an interesting idea. If you are using permanent mulch, it might overcome the disadvantage of not having bare ground in spring. I suspect if you put your heat exchange pipes low in the bed, it might make better use of the soil as thermal mass. Interesting idea.

here's a video I threw together on the solar heater concept. http://www.youtube.com/watch?v=fH9YS2hTIDY

Hi Ivan,

Here in Iceland, we have the same sunless winters, with a milder winter than you, but with many many many freeze/thaw cycles.

The summer is however probably colder than yours.

Key here is not using rocks as heat trap. Does not work that well, except in sunny summer days for ground crops such as squash.

Raised beds does help significantly (raises temperature), when there is another important other thing: shelter from our cold winds. This means huegelbeds would be of great help, because soil here and probably in Sweden too, takes long time to warm up. If its raised, it warms much faster. But provide shelter from winds.

And in a spot just next to the house, where it forms a corner, there is a bed consistently 3º warmer than the surrounding air. So this means that many of the -2ºC freezing days in my garden show a non-frozen soil in that warm spot! That helps A LOT.

Devon Olsen wrote:well not being at all familiar with your particular climate i would say it has some positve affects as youll plan for but the negative effects may outweigh them in that it may cause the temperatures to stabilize between air and soil and when the air is cold it could quickly cool your bed, whereas leaving it closed could providea fair bit of insulation and allow some microbials and fungi to work the very center of the bed in deep winter if it is not installed, that being said i would certainly recommend a few dark stones, particularly on the southside to trap heat as the sun does shine on them and distribute it a bit better

however experimentation will definately be key for oyu as the long sunless winters may cause the rocks to actually cool te area more than warm it... something youll just have to look for and observe yourself, are there any dark rocks i nthe area for oyu to observe the plant life near them?

you might want to put in hotbeds between the hegels. then you can dump in manure, and have the heat transfer to the wood, to keep the temps up. could use your pipes to connect on each side, and if you made em "V"shaped, you could cover the insides with plastic to trap heat when starting plants.

so maybe dig a trench between every other V shaped hegel, and run a pipe across back to send heat to 2 V shaped hegels. ? could prob just use a rock filled trench instead of pipe....

http://www.holon.se/garden/howto/hotbed_en.shtml

http://www.savvygardener.com/Features/cold_frames-hotbeds.html

http://www.motherearthnews.com/modern-homesteading/how-to-build-a-hotbed-zmaz76mazhar.aspx

We live about 100 miles south of the Arctic Circle in Alaska; hugelkultur works quite well here for us so far, and I'm going to build a bunch more this spring. We do have a continental climate here in the interior though, so temps get high in summer. The hugelbeet thawed out and warmed up significantly faster than the ground, and plant growth was spectacular. There are some photos posted in the following threads (the links don't quite work right at this time; they'll take you to the threads but not to the posts, so you might have to do a search on the page for my fine Swedish name to find them).

https://permies.com/forums/posts/preList/17/98169?OWASP_CSRFTOKEN=FM7D-U2AA-6YNO-9CA4-U3YS-YX54-4IIG-9ZWI#98169
https://permies.com/forums/posts/preList/17/98173?OWASP_CSRFTOKEN=FM7D-U2AA-6YNO-9CA4-U3YS-YX54-4IIG-9ZWI#98173
https://permies.com/forums/posts/preList/17/126259?OWASP_CSRFTOKEN=FM7D-U2AA-6YNO-9CA4-U3YS-YX54-4IIG-9ZWI#126259
https://permies.com/forums/posts/preList/17/138645?OWASP_CSRFTOKEN=FM7D-U2AA-6YNO-9CA4-U3YS-YX54-4IIG-9ZWI#138645
https://permies.com/forums/posts/preList/17/147666?OWASP_CSRFTOKEN=FM7D-U2AA-6YNO-9CA4-U3YS-YX54-4IIG-9ZWI#147666

I have not checked this post for a while, and boy am I glad to be back. This forum is amazing with all the feedback you get, cheers everyone!

-Ivan

What about blowing warm air on the bed with the help of solar panels? It will melt the snow early in the spring and heat up the bed, I will still have to wait until there is no risk of frost I guess...

I'v been keen to see how you go with this. Im Aussie but live in Märsta (1 hour north of Stockholm) and have been thinking about trying hugelkultur
at our kolonilott.

Mvh, Stacey

There is still snow on the ground... I will keep you posted

there is some posts on the site from iceland, that may help out too.

gave some plants strengths in freeze/thaw cycles...

I am also very interested in your results, please do keep us informed.

Now the project is started and I would like to know if pine tree logs is fine for using in the beds, these are freshly cut/logged? I will also put down some birch, and some old logs of sallow (salix caprea). The heating pipe idea will not be realized atm...

Also I would like to know what effect the needles might have on the beds? I'm thinking not to use any of them in the beds as they will make the ground acid?

Yes pine is fine. Needles too. Micro organisms over time will stabilise the PH. Fresh log contain a lot of moisture so they are actually preferable to cured wood in this respect.

I would recommend you build the bed not in a straight line but in a horse shoe or keyhole shape. This way, the interior will trap heat, break the wind, and create a micro climate as a result. This will likely extend the growing season.

It would be really interesting to build large hugelkultur beds in a south facing "U" shape, as a sun trap which also blocks the northern wind. The space inside the "U" that gets the reflected light from all sides could be great protected microclimate for many uses: pond, greenhouse....?

The North side of the "U" would be cold and shady, but could be planted in evergreen trees which will reach for the light and further accentuate the solar bowl effect and wind break as well.

Have fun