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Does Compost Need Air? Compost Bins and Air Holes

A properly kept compost bin allows and even increases the rate of decomposition using natural decomposers such as worms, fungi, and bacteria. With rotting plant matter and crawling worms, it’s hard to imagine compost as needing to breathe, however:

Compost bins need to have air holes that allow proper airflow. Compost must have airflow in order to properly break down organic materials. The bacteria and other decomposers need oxygen to perform their function; therefore providing a way for air to get into the compost is crucial.

What is the best way to keep your compost breathing? Keep reading for tips about how and when to aerate your compost so that it will be as healthy and efficient as possible.

Does A Compost Bin Need Air Holes?

A compost bin absolutely needs air holes. Without proper avenues for air to get into the compost, it is possible that the decomposers will be unable to live and, therefore, unable to serve their purpose. Rather than breaking down, a lack of airflow will cause the compost to simply rot, fester and become foul without creating the rich soil compost is intended to produce.

If your compost is housed in a bin rather than a pile, it is critical to make sure your compost can breathe. Building the walls of your compost bin with chicken wire or similar material will allow for air to pass in and out of your compost more easily.

There are a few other ways you can make sure that your compost pile is getting the air it needs.

  • Turn, stir and rotate the compost regularly. Using a shovel or pitchfork, continually turn the compost. While turning a compost pile is probably the most common method of ensuring airflow, it is not the most effective. Oxygen levels in the center of the compost pile are quickly reduced to almost nothing when turning is the only method used.
  • Use a compost tumbler. Essentially, this tool functions like an oversized bingo tumbler, with a handle turning a chamber to keep compost mixed and aerated. Compost tumblers can be bought online at home supply retailers, or you could make your own.
  • Employ a snorkel. No, not a real snorkel, but the same idea. Insert a PVC or similar pipe into the center of your compost. This will allow air to flow in and disperse evenly from the middle to create healthy decomposition.
  • Cover compost during heavy rain periods. Too much water in your compost pile leaves no room for air pockets and can be very damaging to the life of your compost.

Here’s a great video with info about aerating your compost, with more info below:

Does Compost Need Oxygen?

The presence of oxygen is one of the most critical elements of a healthy compost pile. The more oxygen allowed into your compost pile, the more decomposer organisms it can sustain.

If “turning” is the only action you’ve been taking with your compost, it’s probably not getting enough air. Tuning allows the inflow of air only as long as you are physically turning the material. Once the compost is settled back, the oxygen levels in the center of the pile drop to 1% or less in under an hour.

There are other, more cutting-edge ways of increasing airflow and oxygen levels in compost. Using alternative air methods, such as aerobic composting, some composters have been able to maintain oxygen levels of 8% and higher over time.

How Often Do I Aerate Compost?

For most at-home or domestic community compost collections, every 4-7 days. If you’re using a compost tumbler, turn the tumbler once every 3-4 days. As a rule, the more you aerate, the healthier your compost will be.

You can also do quick, easy aerations at random intervals by poking holes through the pile with a broom handle or dowel. This will help keep your oxygen levels elevated and your microorganisms healthy.

It isn’t really possible to over-aerate your compost. Chances are, most home composters are going to turn the pile when they get around to it. In most cases, that is fine as long as you get around to it once or twice a week.

If you notice that your compost isn’t decomposing or is starting to smell worse than usual, it may be a sign that you need to aerate more frequently. These are symptoms of not enough airflow, which kills off the microorganisms responsible for decomposition.

Does Compost Need to Be Covered?

The advantage of covering your compost with a lid or tarp depends on the surrounding environment. For the most part, however, if your compost isn’t exposed to much rain, you do not need to keep the pile covered.

If your compost lives in a heavy rain environment, it’s a good idea to keep it covered. While some moisture is helpful, too much water is deadly for the microorganisms and bacteria at work under the surface of the pile. Healthy compost should be damp and spongy, not soaked.

If you live in a dry, arid climate, then it is more beneficial to leave compost uncovered.If it’s not to protect the compost from rain, a lid or tarp may restrict the airflow to your compost and slow down the rate of decomposition.

Also, compost should be allowed to receive some rain. If you live in a desert environment, it is helpful to water the compost yourself. Remember, however, not to overwater so that the weight of the water does not force out all the air pockets.

Conclusion

Composting, once you know what you’re doing, is a relatively easy, environmentally friendly way to dispose of organic refuse and produce nutrient-rich gardening soil. Ensuring proper airflow to your compost is an essential key to keeping a healthy, living compost bin or pile.

Regular aeration keeps oxygen levels high within the compost, allowing the bacteria, fungi, and other microorganisms to thrive. When decomposers are healthy, active, and plentiful, the rate of decomposition is increased.

There are a variety of creative ways to make sure your compost is properly aerated, all of which can set you on the path to cultivating a healthy, efficient compost pile.

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