I’VE BEEN USING a 55-gallon compost tumbler for five years. It definitely has its advantages, but it has disadvantages, too. People don’t realize that composting in a pile on the ground has some advantages over the tumbler. Here’s what I’ve learned about making compost from both methods.
My composting process
Over the years I’ve developed a composting process that shortens the time it takes to get finished compost. The process has five steps:
1. I place the tumbler where it gets the most sun, so that the compost heats up as much as possible.
2. I load my tumbler with herbivore manure, green weeds, table scrapes, leaves and other plant materials. I never put meat, dairy or oils in the barrel.
3. I try to balance the green (high nitrogen materials) and brown (high carbon materials). The optimum is 40% green to 60% brown. You can sometimes tell if something is high nitrogen or high carbon by the color of the material, but not always. Greens – which include fruit (usually not green), vegetables, and manure (brown) — are typically high in nitrogen. Browns – which include saw dust, mulched leaves and straw — are typically high in carbon.
Most of the time I struggle to have enough greens to balance out the browns. But this year was different because I collected table scraps all winter. This gave me a head start on greens.
As a result of the overabundance of greens, my tumbler smells a little right now. It’s probably because it has too many coffee grounds in it. I’ve started to re-establish balance by adding some of last fall’s leaves, but I don’t want to put too many leaves in too quickly because even mulched leaves will take too long to break down.
4. I try to keep the moisture in the barrel the same as a wrung out sponge.
5. I rotate the barrel once a week. If you spin it too often, the barrel doesn’t heat up because rotating temporarily releases the heat from the center of the pile. If you rotate it too infrequently, you have the same problem because the microbes don’t get enough air. Once a week seems to be the right timing.
My barrel does get noticeably warmer than the outside air. This is partially due to microbes creating heat and partially because the black plastic barrel captures heat from the sun. It doesn’t heat up enough to kill weed seeds. I still have plenty of weeds that come from my compost.
The compost probably doesn’t heat up enough because the barrel simply doesn’t hold enough material. If I had it to do over again, I would buy a larger composter. A 12 cubic foot model would probably be best. It would be large enough to heat up and large enough to hold all the material I could supply.
There are advantages and disadvantages to using a tumbler:
Compost tumbler advantages
- No need to turn the pile to get air into it. Just rotate the barrel.
- Animals can’t get inside and drag food scraps all over the yard. This is especially important in the winter when a compost pile is popular with scavengers.
- The sun heats up a black plastic composter, so the pile reaches cooking temperature faster.
- It’s easier to control the amount of moisture inside the bin.
Compost tumbler disadvantages
- A compost pile on the ground breaks down faster. I’m not sure why, but it probably has to do with the microbes and worms being able to come and go as they please.
- Tumblers are limited in the amount of material they can hold.
- Tumblers typically cost more than homemade compost bins, even if you make the tumbler yourself.
What has been your experience with tumbling compost bins? Do they work for you? Let us know by commenting below.
Related posts you might enjoy: