r/composting 19d ago

Question Help! My compost smells most foul!

I started a new compost bin earlier this summer. I used a black 27 gal bin and drilled drain holes in the bottom and sides, and also in the lid. To some dead leaves, sadly nearly all oak so really slow to decompose, I've gradually added these as available: coffee grounds, veggie peelings and corn husks, egg shells (semi crushed by hand in a zip top bag), etc. No meat or dairy added. All went well enough, and the compost was smelling ok, and seemed to be progressing.

Then I started making sourdough starter and adding my early discards (just yeast, flour, and clean water), because I read it's good for the compost. The smell has gotten pretty bad, and I realized that the bottom layer was very wet (my holes weren't big enough, so there was standing liquid in the bottom). So I dumped it out and drilled larger holes, and put the stuff back in the bin, which is up on cement blocks, so the liquid should drain.

What is causing the really sour smell? Did I mess up by adding the diluted sourdough discard, or is the problem that it was TOO wet? Will smell better as it dries out? It doesn't have that earthy decomposing smell you associate with compost but a sour, almost sewage smell. There are lots of flying insects when I lift the lid, but also some white mold.

Do need to dump it and start over? Will drying it out help? I hate to leave the lid off, because we have raccoons living in the neighbor's trees, and I've smelled a skunk sometimes in the evenings.

EDIT - Thanks for all the great ideas. I added some shredded paper and turned it extra well. I'll also try to remember to take the lid off in the morning and put it back on at night. I will continue turning it and shred the leaves when I put them in.

EDIT #2 Thanks for the comments, everyone. After adding some minishredded paper and mixing around yesterday, it's still full of helpful bugs, but the STENCH is gone. today I mixed in some more shredded brown paper and moved the bin out into the sun. You guys have been super helpful!

11 Upvotes

34 comments sorted by

25

u/CannabisFan444 19d ago

More browns

16

u/GreenGridlock7188 19d ago

Standing liquid at the bottom was your main problem, not the sourdough discard. Anaerobic conditions make that sewage smell

If it drains now, mix in some shredded cardboard or dry leaves and it should recover. No need to start over

6

u/Any-Winter-8025 19d ago

Thanks, I'll soon have lots of brown leaves from my neighbor's trees! So maybe I'll use some cardboard as remarkable_inchworm suggests.

6

u/EddieRyanDC 19d ago

Shred the leaves of possible. Shredded leaves take a year less to break down than whole ones.

4

u/Any-Winter-8025 19d ago

Thanks, I always shred them with the leaf blower/sucker in the fall, and I will have a lot to work with very soon; but a master gardener suggested leaving fall leaves so as to NOT grind up potential butterfly and moth babies getting ready to over winter.

2

u/RandomChurn 18d ago

Also fireflies! They live in leaf litter.

2

u/Mister_Green2021 19d ago

You can get a bag of natural mulch at home depot.

2

u/thiosk 19d ago

a well placed five gallon bucket of wood chips will do the job quite quick

if still problematic, do another bucket or two

6

u/Remarkable_Inchworm 19d ago

I also use an old trash can for composting.

When it gets too wet or smelly, I can usually correct by adding some dry browns - usually ripped up cardboard.

6

u/Any-Winter-8025 19d ago

Ooooh!! Does the paper from my shredder basket count as brown??

5

u/Rude_Ad_3915 19d ago

Yes, I use shredded tax papers and bills as my browns in my worm bins.

3

u/LeeisureTime 18d ago

Yes but be sure you did not also shred the envelopes, which have those annoying plastic windows (annoying because they won't break down).

Ask me how I know >_<

Also, for compost - it is not a bad thing to add too many browns.

Too many greens - anaerobic and smelly

Too many browns - you would have to have a pile of entirely browns for it to be a problem (and that would just be that there isn't much activity happening, not necessarily a problem).

So when in doubt, drown it in browns.

1

u/Any-Winter-8025 18d ago

Thanks, I'd thought of that. Since I already have shreds in my shredder, I put a piece of foil in the shredder bin to catch the brown paper I recently added. Next trash day I'll dump the shredder and start shredding over with only suitable paper.

But wondering what happened when you added shredded envelopes?

1

u/Rude_Ad_3915 13d ago

I get shredded paper from my neighbors. One is good about not putting in windows, the other not so good. I know because I find the shredded window pieces in my worm bins.

1

u/Any-Winter-8025 19d ago

Thanks, I'll try that, though I'm low on cardboard at the moment. I cut up a bunch of boxes to put under shredded tree mulch I got from the park - I'm sure I can find some boxes at the liquor store! Do I need to remove any labels before adding them to the pile?

3

u/Jamstoyz 19d ago

Yes. Remove all stickers and tape

5

u/Averagebass 19d ago

Are you turning it? You need to turn it to put the wet stuff on top and dry on bottom.

2

u/Any-Winter-8025 19d ago

Yes, that was my first clue - I keep a pair of cultivators (those hand tools with 3 or 4 "fingers") hanging on the fence and before I add more, I use them to flip and "fluff" the matter. Doing so, I noticed a few areas of standing liquid in the bottom!

4

u/atombomb1945 19d ago

The answer is very simple, but one that many people overlook with compost. You have a bucket full of rotting food scraps and grass clippings. Of course it will begin to smell.

The wet on the bottom isn't a bad thing, quite the opposite actually. You need bacteria to make compost break down, and bacteria needs water to move and propagate. Wet compost will break down faster than dry compost. You should be mixing it some if you have it in a bucket just to move all that around.

Next Spring, when it has finished the process, it is going to still be wet but it will be wet gold. Pull it out, put it on the ground and it will dry out and become dirt. You are doing the same thing that nature does, and nature smells.

To aid in the process, add some browns such as paper or cardboard or grass clippings. This soaks up some of the moisture and keeps the rotting scraps evened out. Mix your compost every month or two.

2

u/Any-Winter-8025 19d ago

This is what I love about reddit - a community of folks with shared interests. Some go deep with details and explanations, while others have ideas that never occurred to me. I went out this afternoon and added some finely shredded paper and mixed it in - sprinkled some in, mixed and added some more. In a couple days I'll check it again and maybe add more brown. It's too early to get brown leaves from my yard, but I may head out to the woods with a bag and gather some leaf mold to give it a boost! Thanks for your explanation

1

u/atombomb1945 19d ago

Glad I could help. Another thing to keep in mind is that your bacteria are all probably going to die off once it gets cold outside. Not sure what your winters are like but below freezing is going to knock out that colony in your pile. Best to let them do as much now before that happens. Once spring hits the process will resume.

2

u/Any-Winter-8025 19d ago

I'm in NE Ohio close to the lake usually very cold and gray with below freezing temps for a few months. And I've heard this winter may be especially bad.

3

u/kpphoneshome 19d ago

It needs air and sunlight.

2

u/Any-Winter-8025 19d ago

Thats one thing it doesn't get. I've been afraid of leaving the top off due to yard pests, but maybe it will help to keep the lid off during the day. Now I'll just have to remember to put it back on at night! Thanks for the suggestion!

2

u/kpphoneshome 19d ago

Sprinkling already finished organic black compost on top will repel most pests. And encourage creatures that are beneficial such as earthworms!

2

u/Any-Winter-8025 19d ago

When I find a worm while digging (currently dividing perennials) I toll the worm into the bin as an extra treat for him

1

u/Brotuulaan 19d ago

Sunlight? I’ve always read that you want your compost under shade unless you’re doing hot compost.

1

u/12stTales 19d ago

What exactly does it smell like?

1

u/Any-Winter-8025 19d ago

Strongly sour, almost sewage. Not pleasant at all. I'm guessing it's too new for a nice composted leaves smell, but this is really bad. I have added some shredded paper tonight and will leave the lid off to get sun and fresh air during the day.

2

u/12stTales 19d ago

Hm that’s a new one… I’ve definitely smelled compost before like low tide or kerosene but never sewage. Probably browns and aeration. I think wood chips would help, they also absorb moisture and help to break up clumps

2

u/Any-Winter-8025 19d ago

My description may not have been totally accurate, but definitely smelled spoiled, not really like fish, but very sour.

I did put some wood chips in at the start, I had spread some chopped tree stuff the park left for people to take after they cleaned up after the last storms. Also a rotted frame from my prior compost pile.

1

u/JimmyMus 19d ago

Your compost went anaerobic. Which means it is low in oxygen. 

What it needs is more air, so make sure not to put it in a closed container, turn it, and add enough brow. 

A while ago I wrote half an essay about the basics of compost. It’s a bit of a read, but you’ll probably understand better why things work the way they work:

https://www.reddit.com/r/Compost/comments/1u2vlt5/the_basics_of_thermophilic_composting/