Vampire Hugels

This past spring, when putting in my garden for the first time, I made hugels wrong. I knew it was wrong but without getting into all the nitty gritty, I was out of time, out of resources, and most particularly out of dirt. I figured doing them wrong was better than doing nothing because I was more likely to learn something.

So I raked together the large quantity of woodchips (I can hear you cringing) that I had used to kill our lawn. I shaped them into little hügelchen, or molehugels if you prefer, mixed them 50-50 with organic compost I'd bought to get things going, and figured for at least the first year I'd just use them as water-retaining planters while they broke down. So I soaked them well, dug holes in them where I wanted plants, put in organic potting soil, and planted vegetable, herb, and flower starts and seeds.

For a little while everything was fine, and with straw mulch on top I really didn't have to water much (I live in Utah, so this matters). But then the plants stopped growing, many went completely albino, and a bunch died. The hugels just sucked the life out of them.

After much research and experimentation, I discovered that if I watered the plants with diluted urine, they came back to life. Many literally turned green overnight. In the end, we got a bunch of summer squashes, flowers, and herbs, and I have cold season veg out there now.

I'm including a photo from late August, when the urine had taken effect. But you can see how barren the hugels are compared to the surrounding area. It's not because I didn't plant there.

I watered the hugels periodically with a sprinkler through the summer to keep them wet, and they broke down a fair bit but there are still a lot of identifiable woodchips throughout them, so there's a way to go yet.

It was very time-consuming to hand-water all the plants with urine in the end, and I'd like to hasten the decomposition process and see if there's some way to amend them so I can grow more easily in them next year, and even get perennials going. I tried sowing clover, but it barely sprouted and immediately died. (There is a possibility my compost was contaminated with broadleaf herbicide, because bean plants did badly and died even with the "special water," but I haven't tested to be sure, and will do that in the early spring. So let's set that aside till I'm certain.)

I talked to the head gardener at Wasatch Community Gardens, where they teach organic gardening (not permaculture, but local). They suggested amending the hugels with blood meal and try again with nitrogen fixing cover crops, but probably growing will just continue to be hard until the wood chips are decomposed. I wouldn't mind advice on how to get that to happen sooner as well.

So that's the situation. I would love advice on how to improve the situation for next year.

If the wood you used to make the hugel was entirely woodchip, I am assuming that it is the surface area of the wood reacting with the surrounding environment through bacterial/fungal decomposition is robbing you of nitrogen. Traditionally, the large pieces of wood would decompose into large mass sponges that end up holding water.

Is it semi-decomposed already? Perhaps amending with manure/greens and mixing them will help it process down over the non-growing season.

Another option if the chips are still rather intact is to mound them together and try and process it down like a traditional compost pile.

Don't beat yourself up with the rushing and lack of time, this is all about learning! Sometimes we rush things that can't be rushed. Sometimes we take way to long for things that could be done in a moment!

It's probably mainly the nitrogen issue, but it may also be related to the species of tree the chips came from, some can be toxic, or acidic. Both issues naturally improve as the wood breaks down.

I'd probably add a high-nitrogen fertilizer or compost now to speed decomposition, and then again in the spring before planting. Add another layer of straw on top. It may take a year or two to get good, but should be worth the wait.

Where did the straw and compost come from? I found out the hard way with straw this year mine was actually hay that was leftover but same applies. Killed everything. I planted a cover for winter after removing hay and it has broadleaf growing so it didn’t seem to damage the soil as I cleaned it up as quick as I found out.

Where I live if you’re buying “organic” compost it’s from dairy farms. 99.9% of hay where I live is sprayed with weed killer. So that will still be in the compost.

Timothy Norton wrote:If the wood you used to make the hugel was entirely woodchip, I am assuming that it is the surface area of the wood reacting with the surrounding environment through bacterial/fungal decomposition is robbing you of nitrogen. Traditionally, the large pieces of wood would decompose into large mass sponges that end up holding water.

Is it semi-decomposed already? Perhaps amending with manure/greens and mixing them will help it process down over the non-growing season.

Another option if the chips are still rather intact is to mound them together and try and process it down like a traditional compost pile.

Don't beat yourself up with the rushing and lack of time, this is all about learning! Sometimes we rush things that can't be rushed. Sometimes we take way to long for things that could be done in a moment!

Thanks Timothy! Yes, my assumption based on the things I've tried, how much the urine helped, and what I now understand about wood chips in the ground vs. on top of the ground is that the main issue is the decomposition robbing nitrogen. It's semi-decomposed, but there are still plenty of identifiable chips in there. I've been reluctant to break them apart because I have the impression that will set back the mycorrhizae and potentially slow things down. I've had a lot of mushrooms pop up, and in fact had a ton of slime molds in the late spring, so I know I have that going on.

Geez, I forogt about the slime molds. Until I learned how to catch them early, they kept swallowing up my little plants. Yet another issue with the hugels.

Thom Bri wrote:It's probably mainly the nitrogen issue, but it may also be related to the species of tree the chips came from, some can be toxic, or acidic. Both issues naturally improve as the wood breaks down.

I'd probably add a high-nitrogen fertilizer or compost now to speed decomposition, and then again in the spring before planting. Add another layer of straw on top. It may take a year or two to get good, but should be worth the wait.

Interesting, Thom. Both you and Timothy above suggest adding nitrogen to speed decomposition. I didn't know it could work like that, I thought with wood chips it was fungal, and any nitrogen-containing amendment I'd add would be to help the plants survive...

Joe Hallmark wrote:Where did the straw and compost come from? I found out the hard way with straw this year mine was actually hay that was leftover but same applies. Killed everything. I planted a cover for winter after removing hay and it has broadleaf growing so it didn’t seem to damage the soil as I cleaned it up as quick as I found out.

Where I live if you’re buying “organic” compost it’s from dairy farms. 99.9% of hay where I live is sprayed with weed killer. So that will still be in the compost.

The straw was from a small farmer--a friend's neighbor. I suspected it of herbicide contamination for a while, but then I heard this could happen with compost too, and that makes a lot more sense. I used compost everywhere I used the straw including places besides the hugels, and although seeds didn't really come up very well, I didn't have the problem of plants not growing, turning white, or dying. In fact I got tons of tomatoes and cucumbers (in a non-hugel bed), for example.

However, everywhere I used the compost, even if I didn't use straw there, I had almost no seeds come up. Bean plants that did sprout quickly died, and the nasturtiums had cupped and bumpy leaves for a month or two. So maybe the straw was contaminated, maybe it wasn't. But the case is stronger that the compost was contaminated.

Or, since I'm new at this, I might have screwed things up in some other way, like over-mulching and/or not watering enough. And maybe the nasturtiums were having some other problem. I'll test the compost and the straw to find out for sure, since I still have a lot of both left. It was a commercially available organic turkey compost. My memory was Oakdale Farms Organic Turkey Compost. I bought it from someone else who had overbought, but I looked it up online beforehand. So it wasn't from a dairy farm, and my recollection (though I can't find it online now) is that the only manure in it was turkey.

Jae Gruenke wrote:Geez, I forgot about the slime molds. Until I learned how to catch them early, they kept swallowing up my little plants. Yet another issue with the hugels.

So when your plants were small, the slime molds simply grew over top of them?

I had slime mold in my tomato bed one year, but the plants were quite large and the mold didn't hurt them at all. That said, one's ecosystem can make a big difference as to how out of control some things get.

And wrote:

Interesting, Thom. Both you and Timothy above suggest adding nitrogen to speed decomposition. I didn't know it could work like that, I thought with wood chips it was fungal, and any nitrogen-containing amendment I'd add would be to help the plants survive...

I've heard mixed results as to whether urine (lots of nitrogen) speeds up wood chip decomposition. Urine can certainly help growies, and growies can encourage the wood chips to decompose - I'll see roots penetrating the wood in my ecosystem.

You've got a bunch of rows there. It would be interesting to try pouring urine regularly on some rows and not on others and take lots of pictures and see if you notice a difference or not.

That said, mycorrhiza work with plants too, so if you can't get plants to grow in the chips, you loose out on some of the teamwork that microbes and plants do.

And wrote:

So maybe the straw was contaminated, maybe it wasn't. But the case is stronger that the compost was contaminated.

Do you have some extra seeds you could do a test with? Make up some pots and try a variety of seeds including  ones that would be affected by broad leaf herbicides and ones that would not be. There is a practice in some places to spray grain crops with "kill everything" chemicals to get the plants to all ripen at once. If that grain was fed to the turkeys, it would be in the compost, and you might find that grass or wheat will struggle to germinate just as much as the beans would. I would expect that hay would only have been sprayed with broad-leaf chemicals, so if some of the hay is sufficiently decomposed to do a test on it, that might give you good information moving forward.

I have to admit that your description of the reaction of the bumpy leaves on the nasturtiums is similar to an experience I had with a bad batch of horse manure. However, "similar" doesn't mean I was dealing with the same chemical. Whatever it was, it was very persistent. It's on my list to do a serious test again in that area - it certainly grows grass, but I'm not convinced it will let seeds germinate normally, so I should follow my own advice and dig up a few pots worth and give a few of my excess seeds a go.

Was the compost in bulk? I have had a delivery of compost that was still a touch too hot and it really hurt me one growing year. The following year, I had explosion of growth assumedly from the compost now being bioavailable.

I'm thinking a similar discussion found here might be beneficial for your viewing?

Now towards my opinion - Don't try to adjust all these different variables all at once trying to find a root cause. Methodically start working out the most obvious issue to the least obvious. I would let the chips/compost mellow together. The fact you are seeing slime molds mean there is activity happening! I never had slime molds take out plants so I'm wondering if they are just a result of a dying plant or if they in fact took them out. I think a good early season crop to gauge if things will grow in the plot are peas. They also can help fix nitrogen in the soil for later crops. If things are still goofed up, then I'd start being suspicious of the manure and straw. If you have the ability to test either of them for peace of mind that is great but don't scramble around and stress yourself out with it at first.

Timothy Norton wrote:Was the compost in bulk? I have had a delivery of compost that was still a touch too hot and it really hurt me one growing year. The following year, I had explosion of growth assumedly from the compost now being bioavailable.

I'm thinking a similar discussion found here might be beneficial for your viewing?

Now towards my opinion - Don't try to adjust all these different variables all at once trying to find a root cause. Methodically start working out the most obvious issue to the least obvious. I would let the chips/compost mellow together. The fact you are seeing slime molds mean there is activity happening! I never had slime molds take out plants so I'm wondering if they are just a result of a dying plant or if they in fact took them out. I think a good early season crop to gauge if things will grow in the plot are peas. They also can help fix nitrogen in the soil for later crops. If things are still goofed up, then I'd start being suspicious of the manure and straw. If you have the ability to test either of them for peace of mind that is great but don't scramble around and stress yourself out with it at first.

We're on the same page, Timothy. I know nitrogen is a problem, so that's the part I'm wondering if I can do anything about now, as we go into winter. I'll explore the possible contamination issues next spring.

The one thing I can rule out is the compost being too hot. I got a soil thermometer and through the late summer into fall found the hugels consistently 5-7 degrees warmer than the ground, but that's it. And whenever I watered a struggling plant with diluted urine, it recovered literally overnight, which wouldn't have happened if heat was the problem.

As for the slime molds, they literally swallowed up seedlings. I'd mulched with straw but left holes around seedlings, and slime molds would erupt through those holes (I guess they needed the light) literally overnight and be so large they simply swallowed the seedling. I learned to identify the signs that a slime mold was about to erupt on my evening walks, and grab the surface woodchips and toss them on the paved path, and that would prevent the mold from developing and save the plant.

(somehow the quoting function isn't working properly here, but this is a response to Jay Angler's comments)

"That said, mycorrhiza work with plants too, so if you can't get plants to grow in the chips, you loose out on some of the teamwork that microbes and plants do."

Interesting, Jay. I like the idea that my plants are helping the decomposition, and it makes me feel a bit more optimistic about working to grow things in the hugels.

"Do you have some extra seeds you could do a test with?"

Yes, that's my plan. I thought I'd wait till spring, though, as I don't yet have a good seed-starting setup indoors.

Hi I am new here

There have been a few mentions of fungi already, I think, but I just wanted to say that nothing turns wood chips and straw into lovely rich soil faster than mushrooms, with the bonus if you get an edible crop! I'd recommend seeking out wine cap spawn to inoculate those beds; I've heard of people who don't care for mushrooms cultivating them just for the amazing compost.

Hello Jawad!

C. Lee Greentree wrote:There have been a few mentions of fungi already, I think, but I just wanted to say that nothing turns wood chips and straw into lovely rich soil faster than mushrooms, with the bonus if you get an edible crop! I'd recommend seeking out wine cap spawn to inoculate those beds; I've heard of people who don't care for mushrooms cultivating them just for the amazing compost.

Hello Jawad!

Thanks very much for the suggestion! I will do that.