Many of my readers have been breathlessly awaiting the results from my composter-shed experiment (e.g. Post 1899).
Unfortunately, that breathlessness is not explained by the stench of rotting kitchen scraps.
In the winter cold, my tumbling composter is not so much a composter as a mausoleum. It’s the Lenin’s Tomb of potato peels. Each time I visit it to dump in a new batch of scraps, I soberly reflect upon the perfectly preserved remains of ancient meals resting comfortably within. I ponder what that means for the future.
Source for title photo, via Wikipedia: By Russia, Lenin’s Mausoleum or more specifically image, Fair use, https://en.wikipedia.org/w/index.php?curid=48098730
Background
Recall the issue here: I toss my kitchen scraps in a tumbling composter. Three seasons of the year, that works great, and the compost is really desirable for gardening. But when the weather turns cold, the composter stops working, for all intents and purposes. I then have to throw my scraps into the trash, where they eventually become trash-to-electricity “biofuel” when Fairfax County incinerates them.
I refuse to heat my composter with electricity. And I’m not going to bring it inside for the winter. So … how about trying a solar-heated “shed” for it?
Bottom line: Passive solar through double-paned glass, plus insulation, and radiant barrier, together, provides nowhere near enough heat to keep this tumbling composter running during the winter.
I suspect that adding more insulation would be fruitless.
First, the shed does, in fact, keep the temperature of the compost up, when the sun shines. But with a fairly large ratio of surface area to volume, a string of cloudy days allows this to cool right down to ambient temperature.
Second, the resulting “cold snap” kill off any insects in the compost. I like to think of a composter as a place for bacterial decomposition of kitchen scraps. But in fact, I’ve never really known what fraction of decomposition was insect-drive, versus bacterial. Typically, when I open this composter to add material during spring/summer/fall, I can see insects (larvae) working on the contents. But all it took was a few freezing nights to stop all insect activity.
My take on it is that adding an inch of foam board to the existing shed isn’t going to fix that.
What are the other options?
Psychrophilic, qu’est-ce que c’es?
Source: All pictures in this section are AI-generated with the prompt “cold, hungry bacteria”, using Gencraft.com.
Composting small volumes of organic material in cold weather is a common problem. Near as I can tell, the suggested solutions are:
- Compost a large enough volume that the pile stays warm outdoors.
- Store your kitchen scraps over the winter, in some location.
- Move to indoor worm composting for the winter.
- Give up.
I don’t find any of these options particularly appealing. I don’t generate a large enough volume of organic matter for 1) above, and the Virginia climate is not well-suited to 2) above. I can’t depend on the kitchen scraps remaining frozen, outside, in a typical Virginia winter. And I’m not too keen on having five-gallon buckets of garbage sitting around, even if they are sealed. I’m guessing my neighbors wouldn’t be all that keen on my digging a garbage pit in my back yard. At least, not if they knew what I was up to. I don’t want to get into 3) indoor worm composting, though I am finally beginning to grasp the potential advantages of that over traditional outdoor composting.
Arguably, the smart option is 4) give up, per the recommendation on this website.
(Finally, I’ve already dismissed the idea of an indoor electric “composter”, that is, combination grinder and food dehydrator. Just not my cup of tea.
My last gasp at making this tumbling composter work in the winter is to track down some “psychrophilic bacteria”. That’s the term, per this U. Mich. website, for the cold-loving bacteria that break down organic matter even in colder temperatures. (The same website says that a cubic yard of organic matter is the smallest pile likely to continue to hot compost in a Michigan winter.)
First, the idea of cold-tolerant decomposing bacteria is a real thing. You can find it in the scholarly literature (e.g., this reference, for psychrotrophic bacteria).
I have no clue if spiking my compost with psychrophilic/psychrotropic bacteria will work. (As you have probably already guessed, the prefix “psychro”- means “cold”.) Everyone says these cold-adapted bacteria work slowly, but they do continue to work, even in the cold where other bacteria would not.
And that doesn’t matter anyway, until I can figure out where I can buy the little buggers.
I haven’t found anything specific to composting. Apparently the approved solution to winter composting is to have a big enough compost pile. That said, I seem to find two plausible sources.
Pond cold-weather bacteria. The first thing I came across is cold-weather bacteria for (decorative) ponds. Apparently, you spike your pond with these to keep decomposition going in colder weather. Here’s an example. Here’s another example. Amazon offers dozens of choices.
Main-line drain maintainer. It also occurs to me that I can buy stuff at Home Depot that advertises that it spurs decomposition within your main sewer line. Those lines sit at around 55F in this area (although the incoming materials may be warmer). So it’s plausible that dumping that stuff, in my tumbling composter, might aid decomposition.
Of the two, I think the pond bacteria would be the better choice. All of those products appear engineered to break down cellulose. The drain cleaner, by contrast, is advertised to break down “grease, hair, paper, oil, soap scum”. The pond bacterial additives appear to be directly targeting the type of organic matter I’m dealing with, the drain cleaners are not.
The proposed experiment.
As it turns out, I’m going to have to shell out something like $30 to buy some fall/winter pond treatment. And my composter conveniently has two compartments. So I might as well set this up as a proper experiment. I’m going to mix up and level out the materials currently in the two sides of the composter. Add fall/winter pond bacteria to once side. And see if I notice any difference in the remaining volume of materials, one month from now.
I can’t find winter pond bacteria locally, so I’ve ordered some from Amazon. This stuff. Several comments attest to the fact that it works in cold weather. And stinks. And that’s, eh, more-or-less what I’m after.
Results in a month.
