compost question about heat and bad microbes

I recently got a thermometer and can see the compost is getting up to around 92°F in some spots.  To me that is good news, but it is starting to smell a bit worse, as well.  I've since added some more browns and tumbled the tumbler a few times.

Do "bad" microbes heat up compost just like "good" microbes?  Is this what I might be seeing, or is it just the good microbes doing their thing (albeit maybe less of them than required)?

goodtogrow wrote:Do "bad" microbes heat up compost just like "good" microbes?  Is this what I might be seeing, or is it just the good microbes doing their thing (albeit maybe less of them than required)?

Pathogens - "bad microbes" - are generally anaerobic, and they do not cause the compost to become "hot".  If the compost is heated to at least 130ºF it will kill all of the pathogens.  The smell you refer too is one of the keys to making good compost - a foul, or ammonia, smell is an indication of too much nitrogen, and not enough carbon.

Thanks, OhioGardener.  And thanks for your patience with people like me who are just starting out trying to make compost.  It's taking me awhile to get the hang of it.

The smell is a quite ammonia-like, so I'm thinking it is too much nitrogen.

I've added some more browns (pine pellets) and will see how it goes over the next few days.

Well, I feel like giving up.  My compost just isn't doing anything.  There are still lots of clumps of nitrogen-type stuff.  The clumps range in size from a marble to a ping-pong ball, some a bit bigger, and are slightly moist with what looks like gooey grass clippings, vegetable pieces, and small leaves, on the inside.  They are covered with a mix of the pine-pellet sawdust and coffee grinds.

I've broken down as many as I can, but I just can't get to all of them.  I'm worried that every time I tumble the composter it just creates more of these clumps.  I haven't added water for about a week or more now and am still hesitant to do so.  The thermometer says it only gets as high as about 82°F (not 92°F as I wrote before, I read it wrong last time), but that's about it, and only in a few places does it get that high.

I found a piece of savoy cabbage we put in about two or three weeks ago - and it looked like it had been added this morning, practically fresh.

The overall smell of the compost has improved since I put in the dry browns (pellet sawdust) a few days ago.  But the clumps smell really bad on the inside when I break them down.

Anyway, I'm discouraged, not sure what I'm doing wrong, and not sure what to do next.

Any advice?

goodtogrow wrote:Well, I feel like giving up.  My compost just isn't doing anything.  ...< snip > ...

I'm not feeling like giving up yet at all. But I have the compost in the new double tumbler (one side only so far) that is not doing a lot, either.
Measured the temp today, in the 90's.   But I haven't given it any attention, and my son has only added a few bins of kit waste every couple of days and added in SOME of the dry grass I'd collected for him to start, not even wetting anything down or doing anything to put the correct ratios in there.   So it hasn't had a chance.

I know some of what we need to do but haven't had time to address it.  Too many other more important priorities.

Hang in there, GoodtoGrow!

@GoodToGrow

It really sounds like your material has become too wet. The moisture content throughout the compost should be fairly even, and about as wet as a damp rag.

Also, how big is your tumbler? What type is it? How much material is in it? My experience with a smaller tumbler suggests that you need to have a fairly large one to get results.

Some pictures might help us to understand what's going on with your situation.

Good Gardening!

Hi Mark,

It is this composter (37gal):
https://thegardeningdad.com/yimby-tumbler-composter-review/

Yes, you're probably right about it being too wet.  I'm letting it dry out now and not touching it for awhile.  Haven't added any water for about a week.  I'll get some pictures soon.

The one compartment is about 80% full, the other is empty.

If it was me, I'd keep turning it every day, if it isn't too much effort. You want it to dry out evenly.

For perspective, that's about the size of a trash can. But it's about half filled. And it's suspended in air where it's surrounded by cool air. I see that your overnight temperatures are sometimes still in the 50s (well, if I did the math right).

What I've done in similar situations  is to dry everything out by spreading it on a tarp for a few days. Then using a chipper to grind it down. Then rebuilding and remoistening the stack.

Thanks, Mark.  Yeah it's still around 50s overnight here.

The compost doesn't seem all that wet to the touch, it isn't much more wet that a damp rag, but I think it's just saturated all the way through.

Only trouble with turning it is that it still might create those clumps, but you're probably right - it needs to be done to dry it more evenly.    I've used a hand rake to break it up and fluff it up, so I'll keep doing that and turn it every day.

Interesting idea about the tarp - I will keep that in mind but probably only do it as a last resort since it isn't in a very convenient spot to do that type of thing, but we'll see. It's definitely a good idea.

Thanks again, much appreciated.

goodtogrow wrote:The compost doesn't seem all that wet to the touch, it isn't much more wet that a damp rag, but I think it's just saturated all the way through.

Grab a handful of the compost material, and squeeze it as hard as possible.  If more than one drop appears, it is too wet.

Only trouble with turning it is that it still might create those clumps, but you're probably right - it needs to be done to dry it more evenly.    I've used a hand rake to break it up and fluff it up, so I'll keep doing that and turn it every day.

Unless you are adding new material, there is no reason to turn it every day.  Allow the compost heat up, and after it gets up above 140F slowly turn the tumbler 4 or 5 rotations.  Don't go too fast, and don't go too long.

Interesting idea about the tarp - I will keep that in mind but probably only do it as a last resort since it isn't in a very convenient spot to do that type of thing, but we'll see. It's definitely a good idea.

Alternately, if it is too wet leave the door open on the tumbler to expose the compost to the sun so that it will evaporate some of the moisture.

OhioGardener wrote:Alternately, if it is too wet leave the door open on the tumbler to expose the compost to the sun so that it will evaporate some of the moisture.

Thanks, yup, that's exactly what we're doing right now.

Unless you are adding new material, there is no reason to turn it every day.  Allow the compost heat up, and after it gets up above 140F slowly turn the tumbler 4 or 5 rotations.  Don't go too fast, and don't go too long.

That's the thing, though, it's not heating up at all.  It was at 64°F around noon today according to my thermometer (tested in three different places and depths).  That's down from the 82°F I got last week.  I'm going to keep tumbling it for now in an effort to aerate it as well as fluff it with the hand rake, and leave the doors open.

Grab a handful of the compost material, and squeeze it as hard as possible.  If more than one drop appears, it is too wet.

Good to know, since I thought it was supposed to have a few drops come out.

Also, I think the coffee grinds were too wet when I added them, maybe I should have dried them off before adding them.  Also, the pellets fluffed up (I put too many in) and made a 6" layer of sawdust with a layer of coffee grinds between the pellets.  Actually, there were two layers each of pellets and coffee.  I have a feeling that kickstarted anaerobic microbes in the coffee back then and they've only continued since, leading to where I am now with it.  Now the coffee and those anaerobic microbes are all throughout the entire compost, it seems.

Which leads to my next question: with a tumbler should we mix browns and greens together first before adding?  Everywhere I've read that things should be added to compost piles in layers.  But they say that mostly for compost piles, not tumblers.  When I think about it, it seems that pre-mixing browns and greens would be the way to go in a tumbler because after the first tumble they get mixed together anyway.  And as far as "surface area", there is more surface area contact between the browns and greens when they are pre-mixed together rather than being in layers.  What do you guys think?

goodtogrow wrote:
Which leads to my next question: with a tumbler should we mix browns and greens together first before adding?

I've never done that.  I dump in a 5-gallon bucket of juice bar pulp, then dump in a quart of pine pellets and tumble it a few times.  The pine pellets get blended with the pulp, and absorb the moisture from it. Then the microbes go to work on it.   A day or two later I might dump in the kitchen scraps from the house, throw in a cup of pine pellets and tumble it a few times.  The microbes continue working on it. These processes are repeated until the tumbler section is full, and then no more is added to it. Just tumbled every few days to keep the compost mixed.

Question: You don't soak the pine pellets before adding them to the tumbler, correct?  The dry pine pellets dumped into the tumbler absorb the moisture from the coffee grounds, etc., and keep it balanced.

OhioGardener wrote:I dump in a 5-gallon bucket of juice bar pulp, then dump in a quart of pine pellets and tumble it a few times.  The pine pellets get blended with the pulp, and absorb the moisture from it. Then the microbes go to work on it.

Okay, yeah, that's basically what I mean.  I was thinking I needed to layer things carefully, but apparently not.

Question: You don't soak the pine pellets before adding them to the tumbler, correct?  The dry pine pellets dumped into the tumbler absorb the moisture from the coffee grounds, etc., and keep it balanced.

I did once (I think you mentioned to?) but since then I haven't.  Actually, the first time I didn't, when I got the 6" of sawdust after watering it.

After having fluffed the compost with the hand rake, crushed as many clumps as I could find, and left the doors open all day, I realized another thing: the container was too full.  When I tumbled it there was too much in it to mix properly.  The compost on the bottom part (opposite side from the door) was compacted and more wet - so I dug it up a bunch and threw about 40% into the other container.  This now allows for much better mixing of the compost as it is only about 60% full, and that seems like a good amount.  Also because the air vents aren't as covered now...

And when breaking up those clumps it is clear they are mostly coffee grounds and uncomposted leaves (originally "dry brown" leaves).  When I squeezed a large clump, lots of water came out (20-30+ drops), yet the rest of the compost was just damp.  Squeezing a handful of that yields no water at all.  It all has that vaguely damp smell, not as bad as it was last week, though.

I think part of the problem was that I've been watering the compost after adding anything, which doesn't seem to be correct, at least based on what you're describing, OhioGardener.  And I think the coffee I added was still too wet and compacted.

So I think I need to somehow dry it all out.  Maybe I do need to dump it out on a tarp like Mark mentioned and meticulously break up all the coffee clumps by hand, dry it all out, and then put it back in...?  I also threw in a few handfuls of pine pellets again today.

goodtogrow wrote:After having fluffed the compost with the hand rake, crushed as many clumps as I could find, and left the doors open all day, I realized another thing: the container was too full.  When I tumbled it there was too much in it to mix properly.  The compost on the bottom part (opposite side from the door) was compacted and more wet - so I dug it up a bunch and threw about 40% into the other container.  This now allows for much better mixing of the compost as it is only about 60% full, and that seems like a good amount.  Also because the air vents aren't as covered now...

If the air vents are blocked, that is a major problem.  In order for the microbes to be able to break down the compost, three things are needed:
1. Food source -- Approx 60% Browns, 40% Greens
2. Air -- If microbes exhaust all the oxygen, they die
3. Water -- Microbes can only be mobile in water

If the air vents are blocked, the microbe will quickly use all of the oxygen and the compost will quickly become anaerobic.

And when breaking up those clumps it is clear they are mostly coffee grounds and uncomposted leaves (originally "dry brown" leaves).  When I squeezed a large clump, lots of water came out (20-30+ drops), yet the rest of the compost was just damp.  Squeezing a handful of that yields no water at all.  It all has that vaguely damp smell, not as bad as it was last week, though.

Those clumps or balls of material are anaerobic inside -- too much water and not enough oxygen -- and that is the source of that "vaguely damp smell".  For example, that clump of coffee grounds and dry leaves would be composting if they had the proper balance of food, water, and air. If they are missing any one of the three they won't compost - in this case that clump is missing air and is saturated with water. When they get back in balance they will compost.

OhioGardener wrote:If the air vents are blocked, the microbe will quickly use all of the oxygen and the compost will quickly become anaerobic.

Do I need to keep the center aerated metal axis free between tumbles on the new Lifetime composter? 

Been following this thread, a week in and measuring temps, it's only 97F.  (Rubbermaid type cabinet next to it is over 100F same time.)

But I know my son did not load it properly, with enough or the right type of browns.  The wire-like grass I raked quickly in the field last week, and set there by the tumblers (all I had time for that day) was not shredded. Just tractor mowings, so 12" long for instance.  And various cardboard pcs 4" average. 

Just started the one tumbler a week ago, and it's already heavy, he says it's getting full.  It was collecting gnats after a few days, he wasn't adding enough browns.  So on Friday,  I just dumped all the grass, half a peat moss bag full (which was damp and hot already from sitting there in the sun and rain) into the tumbler on top and the gnats got better.  After sitting a couple of days with the grass on top, I tumbled it yesterday. 

But then I think my son took out another pail (12qts) of kit waste.  That's when he said it was getting full... 

We know we need to work on this and I asked him to watch a class I have on composting.  We have the tumbler, two older square bins, and the new truckbed-liner area for open composting.

Soose wrote:

OhioGardener wrote:If the air vents are blocked, the microbe will quickly use all of the oxygen and the compost will quickly become anaerobic.

Do I need to keep the center aerated metal axis free between tumbles on the new Lifetime composter? 

I don't have a Lifetime tumbler, so don't know how that is designed and can't suggest the best way. It is very important that the vents are always open while the tumbler finished turning.

On my Jora JK-270 tumbler there are two vents on each end, and I always ensure that after turning the tumbler it is always parked with one of those vents on the top and one on the bottom. Due to the insulation inside the tumbler, I do have to periodically clear the compost out of the vent, though, to ensure there is always good air flow.

I do understand about the air, I was only meaning the air vents aren't blocked now after having fluffed it up (since the compost grew in volume after fluffing).  I was only talking about that immediate situation yesterday; part of what prompted me to move some of the compost, since the composter wound up being practically full after fluffing.  The vents have otherwise always been unblocked, open, and above the level of the compost, even after turning, so that hasn't been a problem.