Sawdust saturated in hop slurry

I have access to hardwood shavings and hop slurry, and am hoping to combine them for composting. Weeds and kitchen scraps will also be included, and I can source coffee grounds from a local business, so it won't only contain hardwood shavings/sawdust as the solids in the pile. But around 90% of the pile will be fine woody material saturated with hop slurry.

I mixed up a trial pile at around 2 cubic feet (inoculated with some mostly finished compost), and 3 days in it is steaming when turned and has my yard smelling like an IPA. So that makes me think that it can hopefully turn into compost on a reasonable timeline, but will the lack of diversity in the inputs cause issues down the line? I'm considering attempting to use some of the bags of wood shavings as human-sized mushroom grow bags as a sort of value adding/pre composting step, but mycology has never been my strong suit.

What magnificent resources! How much can you get?

I think you are wise to be cautious though. I don't believe hardwood shavings will quickly break down in a compost heap, so mixing a lot into soil will drag the whole system down.

You can certainly ferment them, soak them in compost tea, and use them as a top mulch that could be raked off and reused for more than one season.

I like your idea of using fungi to further decompose the shavings. If you can grow fresh edible mushrooms in the process, that's a double win.

Currently about 32 cubic feet of the wood shavings, and I'm going to bring in more hop slurry once I've figured out how I'm ultimately going to use it. It's a pretty intense smell and I have close neighbors so I want to try everything out in small batches first. The hops are pretty much unlimited, though, I'm surrounded by breweries.

I like your idea of treating it and then using it as a reusable mulch, kind of a more biologically active micro-woodchip. I'll try out some treatment options over the next few weeks and report back

Lucky! I am envious.

Wood shavings will be incredibly rich in carbon, persisting for some time, so it is an excellent candidate for mulch. While it won’t fully decompose from the hop slurry, I’m sure the boost of nitrogen will help start the process of turning it into organic matter.

I would recommend with your experiments to add untreated shavings on top of your slurried shavings to help mitigate offgassing. A carbon ‘hat’ might cut down on the stink you are seeing.

If you let the pile cook for some time and then open it up, I’m sure you will start seeing signs of composting/fungus breaking it all down. Those shavings might be a great candidate to grow some mushrooms like wine caps if you can any to further develop organic matter in place via mulching.

My experience with sawdust and shavings in simple composting toilets includes some of the following observations and learnings:

Shavings break down MUCH slower than finer sawdust, remaining somewhat intact after a urine-soaked year in a pile of poop. If you can get sawdust rather than shavings, you may find that you end up with compost after much less time and fewer steps of mixing, turning, and remixing.

When I mix used coffee grounds and sawdust (at least 4x sawdust to grounds), it heats up quickly and stays warm or hot for a few weeks, but then stalls at a grey sawdust stage. This seems ideal for cover material for our compost toilet.

I get sawdust in big woven plastic sacks, so I put an empty sack next to a full one, and transfer the sawdust over, layering/mixing in coffee grounds and occasional autumn leaves, removing junk that comes in the sawdust, and sprinkling water in gradually to get the sawdust all damp. The sawdust being hydrophobic is a bit of an issue, but after a few days it gets damp and the mix heats up. With slurry the moisture issue should be easy.

For your purpose, if you want finished compost, I think you might have good results mixing it a second time with more hops slurry and coffee grounds after the first round has cooled down. Especially if you are using shavings rather than sawdust, this might be necessary. You'll do a first round, learn and change your method, and eventually you'll have a lot of compost. Might take a couple years to get there, though, if you're using wood shavings.

Rebecca Norman wrote:For your purpose, if you want finished compost, I think you might have good results mixing it a second time with more hops slurry and coffee grounds after the first round has cooled down. Especially if you are using shavings rather than sawdust, this might be necessary. You'll do a first round, learn and change your method, and eventually you'll have a lot of compost. Might take a couple years to get there, though, if you're using wood shavings.

Thank you so much for your input :) hearing how long it takes this stuff to break down for you in a humanure situation was a bit of an eye opener for me, so I really appreciate you giving me a bit of a starting recipe to modify off of as I go.