Lifespan of Hugelkultur bed?

So I see plenty of productive beds in the first few years from articles and videos, but what about the long term? I would imagine the zone, rainfall, amount & type of wood used would effect this. Is this just a 5 year system? Then you have to dig out the core of the bed and add more wood? From what I have learned about the beds the most exciting part is how you have a system with little watering needed since the wood acts like a big sponge (once it decays enough). Is this really a "permanent" idea? Thanks!

Daniel Johnson ; It depends on the size Depth of the mass of the buried wood, while there may be some loss of mass the compost and other soil amendments
added to Your bed - for example more soil added on top of the green cover you chop- and-drop, to give new seedlings a head start before the 'weeds' push
through from below - all of these practices show keep your "raised bed'' full to over flowing. a shallow layer of wood mass might need some supplementation
after several years !

Generally you would not construct your HugleKultur Bed over a bed of gravel, given that you have constructed your Bed or Mound over a layer of clay

or other semi-permiable soil (especially if included on a slope as part of a swale system) you should be improving the water retainability in the whole area !

See link below :


https://permies.com/t/32725/sepp-holzer/Sepp-Spring-Terrace

for the Good of the Crafts ! Big AL

As you look at the top of the Hugelkultur page, you see a 2 minute video, taped by Paul Weaton. The person being filmed is Mark Van Der Meer and this was a bed he planted years ago (I think). He just piled on some Spruce branches and some extra fill dirt.

If you need a little more proof that this can last for a while, travel a bit north of your location to the Olympic National Park/Forest on the Olympic peninsula in Washington State. If you walk around in the Hoh forest, you will realize that there are several trees growing out of trees. It looks like (in some cases) an old growth tree (Doug fir, hemlock or something) died a few hundred years ago and eventually fell to the ground. There, it may have decayed for 30 to 60 years before trees started to grow out of them (these snags were not covered by dirt but by moss and fungus). Some of the trees growing out of old dead snags that I saw in the Hoh were as much as 80 to 100 years old, but the base was still recognizable as an old fallen tree.

My point is, the wood in a hugel bed should not be thought of as just a water holding package (mostly 5 to 10 years) but a soil creating device that will become good water bearing soil for the next 20 to 30 years. The original average diameter of the wood going into the pile will determine the longevity. That, and things like water load, local temperatures, number of plants growing out the the pile each year, elevation and so on. I would say, however, it would be a pretty safe bet to turn the walkways into piles and the piles into walkways every 7 to 10 years. If you do this for 4 or 5 decades, you will have generated a huge amount of the ultimate soil (with or without amendments).

Don K. Is this the hugelculture page you were referring to ? https://www.youtube.com/watch?v=Sso4UWObxXg#t=20

Daniel J. : Don K. raises some very good points The picture that follows shows a approx 30 year old tree that sprouted/rooted/ and grew on a old rotted stump.


http://www.rondeauprovincialpark.ca/photo-gallery/

Upps! That did not come out as scripted. Scroll down to the center picture 4 or 5 down and click on the picture !

Try this : http://www.rondeauprovincialpark.ca/wp-content/uploads/2011/04/Yellow-Birch-Nov-11-2ar-1024x682.jpg


This is a commonly seen event in areas well seeded by nature to yellow birch, often so many will have this as a common feature making that clump of trees looking
like a field of ENTS, uprooting themselves to go for a walk-about !

I too have seen massive trees growing on top of downed trees in the pacific northwest and can only believe that even a shallow burial in rich humus makes a vast
difference! So size of material and amount of material buried make the difference in how long your Hugel Bed will last ! For the Crafts ! Big AL

Allen L.
The video I was referring to was . The others are also there, but they only show peoples hugels as they are built or a year or two after. Of those videos, this hugel bed appears to be the longest lived.

I looked at the picture. Yea, it is mostly what I was talking about, just at a much smaller scale than at the Hoh forest. So, I looked through my vacation pics of us going through the Hoh a few years back. My wife is standing in front of a nurse log, obviously fell at least 100 years ago. The nurse log comes up to her shoulder and you can tell this was a fallen log still. I am posting the picture, I painted out my wife to protect the innocent.



She is standing in front of a nurse log that is sustaining 3 or 4 trees the size you see in the picture.

The point I am trying to make is that there are many years of soil generating that will come from a hugel bed. As the wood decays the wood will go from Nitrogen gathering to Nitrogen releasing. It will capture many other minerals that root systems will leave there. Water? Yes, but also soil generation. I would say after 8 to 10 years make the paths the mounds and the mounds the paths (don't dig up the original beds). Then after 10 more years, you can take a bull dozer to the whole thing and spread out all this rich soil in an area 2 times the size and make two times as many piles or a much larger garden. If there are bits of wood in that pile, save them for the new mounds. Or, never bull dose it. If you just smooth out the soil after 20 years, you will have very rich soil to plant in that will still hold a good amount of water.

I think that a lot of the big people (Paul Wheaton, Sepp, Geoff) who do this are too busy to monitor all the piles they have made over the years to make several videos about it. And we need a few decades worth of people making them reporting here at the forum.

Another point about this is, you can put as little or as much effort into these mounds as you want and they will still work year after year for decades.

I modified a hugel bed ~3 years after building it. It was a pain in the ass to water in the very dry summers here, too much erosion, probably in part due to inadequate cover-cropping; last fall I put log walls around it to use as a raised bed.

It was originally built with logs around 6" in diameter; alder, maple, and a bit of coniferous stuff.

When I dug all the way back to ground level on one end, before enclosing it, the majority of the wood was gone, transformed into soil much better than what I had started with. What was left was porous, mostly in small chunks, which could be squeezed in one hand to wring out water. It seems to me that after a max of 5 years in my area there would be effectively no intact wood recognizable as such, making this a reasonable time to rebuild. However, the much improved soil in the old hugel didn't really seem to need more help; I used the available wood to build another hugel nearby, instead.

Dillon Nichols wrote:I modified a hugel bed ~3 years after building it....

When I dug all the way back to ground level on one end, before enclosing it, the majority of the wood was gone, transformed into soil much better than what I had started with. What was left was porous, mostly in small chunks, which could be squeezed in one hand to wring out water. It seems to me that after a max of 5 years in my area there would be effectively no intact wood recognizable as such, making this a reasonable time to rebuild. However, the much improved soil in the old hugel didn't really seem to need more help...

I had a much similar experience, except i had no issue with irrigation. After 3 years only the largest chunks of wood remained, but the soil was almost perfect. I happened to get some video of the process... This was too small of a bed to make any conclusions, but I was certainly encouraged to build more beds.