Keith has been involved in the gardening and landscaping industry for the past 21 years. From a jobbing gardener to running his own landscaping services....
Gardening Latest and its partners may earn a commission if you purchase a product through one of our links.
In colder climates, where temperatures can often drop below freezing, composting can be a challenge. The question then arises do compost tumblers work in the winter? In short, the answer is yes. In fact, they work very well. This is because a compost tumbler is one of the most effective ways to aerate the compost and create an oxygen-rich environment, a key component of creating heat in the pile.
Many gardeners have invested in compost tumblers to improve their composting process. However, they are often unsure if their compost tumblers will work in the winter, or whether compost tumblers are the best for winter decomposition. Keeping your compost going through the winter season is always a good idea as it can provide you with a fresh source of finished compost ready for your spring planting program.
The problem with winter composting is that of cold weather. If the temperature falls sufficiently it adversely affects the decomposition process. This will have a considerable impact on the likelihood of the compost being ready for the spring. This is why compost tumblers are great for winter. If set up correctly, they can change the dynamics of the winter composting process, and mitigate the effects of the cold weather
Understanding the Composting Process
The key to successful winter composting is understanding the composting process. Composting is a result of a chemical reaction between the carbon and nitrogen content of your pile. This causes heat, allowing the fungi and beneficial bacteria microorganisms that break down the organic matter, to multiply. The speed of the process can be controlled by the amount of oxygen present, which is provided either through aeration or turning the compost.
The effectiveness of your composting process comes down to generating and maintaining heat in your compost pile in order for the microorganisms to multiply and consume the organic material and turn it into humus (finished compost). A considerable drop in the outside temperature can cause the temperature inside the pile to drop, slowing down the whole decomposition process to the point where, with certain composting processes, it can stop altogether.
Why Compost Tumblers Can Improve the Effectiveness of Your Winter Composting
Compost tumblers have several advantages over more traditional forms of composting. They tend to be a cleaner, more practical, and simpler way of composting than more traditional. They also allow an easier and less exhaustive method of turning your compost. In addition, the very nature of their design and the way they operate makes tumblers an ideal solution for winter composting.
How Is a Tumbler Designed?
A compost tumbler is designed to mimic the conditions found in nature. The tumbler is a drum that is turned on its axis, allowing oxygen to circulate and speeding up the composting process. The exterior of a tumbler is typically made of plastic or metal, and the interior is lined with perforated walls that allow air to circulate.
Most compost tumblers have a turning mechanism, such as a handle or crank, to make it easy to rotate the drum. Better models of tumblers may also have insulation to retain heat and moisture and holes in the surface of the drum. These allow air to flow into the drum and help with drainage. The better you control moisture and airflow the more efficient the composting process.
How do Tumblers Work
Composting tumblers are designed to allow you to turn your compost more easily helping maintain the heat that is produced during the composting process. Most tumblers have mechanisms that make rotating them simple. When the drum is rotated, the waste within is turned over or “tumbles,” adding air pockets to the decomposing organic material and creating a better aerobic environment. This allows the compost to have more oxygen infused circulating throughout it thanks to the vent holes. The combined effect of all of these variables is to hasten the production of compost that is ready to be used.
When you compost in a tumbler, the turning of the bin aerates and oxygenates the material. As a result of this constant turning process, temperatures inside the tumbler are always higher than they would be if composting were done on an open pile. This high temperature helps to prevent the compost from freezing and results in better decomposition rates.
Another benefit of compost tumblers is their ability to help break down materials quickly. The rotation creates friction that helps loosen organic material. This prevents materials from sticking together and forming clumps which would slow down decomposition.
How Tumblers Help with Moisture Control in Winter
The main advantage of a tumbler over other methods is that you can control the moisture level in your compost. Composting requires enough moisture to encourage and regulate microbial activity.
However, too much moisture can cause problems as the presence of an excessive amount of moisture results in a reduction in the amount of oxygen. This is because oxygen diffuses far more slowly in water than in air. The reduction in oxygen will reduce the heat and slow the decomposition process.
One common issue with composting in winter with traditional composting is that the pile can become saturated through frost or snow melt. The advantage of a tumbler is that it is easier to control moisture than in a traditional pile, as it’s often easier to add water and amendments like sawdust or shredded bark to control levels. This is more so the case in winter than with summer composting as, by its design, a tumbler is better protected from the elements and somewhat insulated from the cold weather.
More Effective Winter Composting
As we have already noted, composting induces a chemical reaction between carbon and nitrogen (brown and green material) present in your pile or tumbler, raising the pile temperature. Beyond moisture and oxygen, there are several factors that play a crucial role in regulating the temperature, which are particularly important to get right during winter.
1# Carbon to Nitrogen Ratio
The carbon to nitrogen (C/N) ratio is an important factor in determining the heat inside the compost pile. The ratio depends on the type of composting that you are doing with cold composting usually having a ratio of between 35 and 40:1 (C/N) and hot composting between 25 and 30:1 (C/N). The lower the carbon content the higher the temperature the pile can reach.
As tumblers allow easy turning you are likely to be using them for hot composting. When composting over the winter periods it is best to try to achieve a ratio between 25 to 30:1 (C/N) to help generate sufficient heat for speedy decomposition
2# Particle Size
One of the golden rules of composting is the smaller the particle size the quicker the decomposition. This is because the more of the organic material’s surface area that is exposed to the microorganisms in your active compost the faster the decomposition process. Furthermore, shredding the material prevents clumps of bigger debris from developing, allowing for improved air circulation inside the pile.
When preparing the organic material for your tumbler, whether it’s carbon-rich materials such as dry leaves, cardboard, and woodchips or nitrogen-rich materials such as kitchen scraps, other organic kitchen waste, or grass clippings, it should be shredded or cut up into the smallest pieces. This will help the microbes decompose the matter in the composter more quickly.
3# Air Circulation (Turning)
Together with the carbon-to-nitrogen ratio, the amount of oxygen that circulates inside the compost pile has the biggest impact on the internal temperature of the pile. Oxygen is added through turning, the more oxygen that is added the hotter the pile should get and the faster decomposition should be.
Whereas in a traditional pile turning in the winter can be difficult in freezing conditions and can also result in moisture ingress into the pile. With a tumbler, it is only a question of turning a handle, as there is no need to expose the composting material to the elements.
Do Compost Tumblers Function in Freezing Conditions?
The only negative would be if it was so cold as to freeze the tumbler mechanism but if it is well-maintained this shouldn’t be an issue. If you do find it frozen a hairdryer should be able to unfreeze it quickly.
4# Batch Control
One of the easiest ways to slow down the composting process is to continually add material to your compost and this is especially true of composting with a tumbler. It might be very tempting to throw the latest shredded paper, food scraps, other suitable food waste, or any other organic material that will compost into the tumbler, just to get it out of the way. This, though can affect not only the carbon-to-nitrogen ratio but will also increase the volume of material in the compost bin, extending the period of time before you have useable humus.
It is good practice to prepare batches of material for composting. If you manage your tumbler correctly you should have finished compost within three months and can then move on to the next batch.
If you are looking to use more traditional composting methods over winter you will need to carefully insulate your pile and protect it from elements and moisture ingress. Although you can cover your pile with a tarpaulin it may not always be enough and you may have to surround the pile with polystyrene blocks to properly insulate. There is though always a danger of water getting into the pile when you uncover to turn.
These are issues that a tumbler largely solves. Decent tumblers are insulated and the fact that the drum is a self-contained unit helps prevent moisture ingress into the active compost.
Summary: Do Compost Tumblers Work in The Winter?
Composting efficiently year-round has its challenges. There is no doubt that in colder months when temperatures can often drop below freezing in some climates, keeping your compost active can be difficult.
There are methods of composting in winter such as vermicomposting that can be effective but they require carefully manage piles or a liking for worms. However, by using a compost tumbler you can pretty much carry on the same process all year round and it will protect and insulate the active compost from the weather, ultimately making your winter composting process much more effective.
So in answer to the quest as to Do compost tumblers work in the winter? The answer is an emphatic yes!, If you have one you should use it.
- Cornell University, Tom Richard: Excess Moisture