Everything that is organic smells like something but a compost should not have an unpleasant or strong smell. A compost should have an earthy smell, if not it shouldn’t at-least be strong and unpleasant.
If the compost is producing an unpleasant odor, it could indicate that the balance of ingredients is off, or that the pile is not getting enough air, or that the pile is too wet. Additionally, if certain types of food scraps are added, such as meat or dairy products, it can create an unpleasant smell and it’s not recommend to add them to the compost pile. It is important to keep in mind that a little bit of odor is normal, but it should not be overpowering. In other words, if your compost smells bad then there is surely something bad going on with the composting process.
Table of Contents
Why a compost smells bad?
Lack of Oxygen in the Compost
Lack of oxygen in a compost pile can slow down or halt the decomposition process. Oxygen is necessary for the microorganisms that break down organic matter to survive and thrive. Without enough oxygen, the microorganisms will die or become dormant, causing the composting process to slow down or stop. Additionally, anaerobic conditions can lead to the production of unpleasant odors and the release of methane, a potent greenhouse gas.
To maintain optimal composting conditions, it is important to regularly, in every 3-4 days, just turn and aerate the compost pile to ensure that it has enough oxygen.
Excess Moisture and Wet Compost
Excess moisture in a compost pile can lead to anaerobic conditions(lack of oxygen), which can cause a foul odor. When a compost pile is too wet, it can become compacted and air cannot circulate properly and the compost becomes waterlogged the bacteria that are responsible for breaking down the organic matter may not have enough oxygen to survive.. This lack of oxygen can cause the organic matter to break down in anaerobic conditions, which can produce odors such as a sour or putrid smell. Additionally, anaerobic conditions can also lead to the growth of harmful bacteria, such as E. coli, and can produce methane gas, which can also cause an unpleasant smell.
To fix this problem, you can try turning the compost pile to mix in more dry materials like cardboard pieces, or adding more brown materials such as straw or leaves to absorb the excess moisture.
Also after adding water into the compost, tap the compost box on the floor couple of times to drain the excess water from the compost.
Turning the compost can also help mix up the compost materials also drying out the excess water.
Not Enough Browns in the Compost
If there is not enough “brown” material (i.e. carbon-rich materials such as dead leaves, straw, or sawdust) in a compost pile, the decomposition process can become imbalanced. Brown materials provide the carbon that the microorganisms in the compost need to survive and break down the organic matter. Without enough brown material, the compost pile may become too wet and compact, leading to anaerobic conditions and the release of unpleasant odors. Additionally, without enough brown material, the compost may not have enough carbon to balance out the nitrogen from the “green” materials (i.e. grass clippings, food scraps, etc.) in the pile. This can lead to an excess of nitrogen in the compost, which can cause it to smell bad and can also inhibit the growth of plants if the compost is applied to a garden or lawn. To ensure optimal composting conditions, it is important to maintain a proper balance of brown and green materials in the compost pile.
Too much greens
If there is too much green material (such as grass clippings or vegetable scraps) in a compost pile, it can lead to a number of problems. One issue is that the pile may become too moist, which can lead to anaerobic decomposition and the production of unpleasant odors. Additionally, too much green material can lead to a nitrogen imbalance in the pile, which can slow down the decomposition process. To correct this, it is important to add a balance of brown material (such as leaves or straw) to the pile to help absorb excess moisture and provide a balance of carbon to nitrogen. Another solution is to use a compost tumbler which allows you to easily mix the compost and have better control of the greens and browns ratio.
Meat and Dairy Products in the Compost
Meat and dairy products should not be added to a compost pile because they can attract pests and animals, as well as cause unpleasant odors. Additionally, they can contain pathogens that may not be fully broken down during the composting process, which could potentially be harmful to plants or animals. If these types of organic waste need to be disposed, it’s recommended to use a commercial composter or a local municipality service that can handle and process it properly.
Meat and dairy products are also high in nitrogen, which can cause an imbalance in the carbon-to-nitrogen ratio of the compost pile, which can slow down the decomposition process. It’s best to stick to adding plant-based materials like fruits, vegetables, leaves, and grass clippings to the compost pile.
Good Bacteria missing in the compost
A lack of beneficial bacteria in a compost pile can result in a slow or incomplete decomposition process. Beneficial bacteria play a crucial role in breaking down organic matter and converting it into nutrient-rich compost.
There are a few reasons why a compost pile may lack beneficial bacteria:
- Insufficient moisture: Beneficial bacteria require moisture to survive and thrive, so a dry compost pile may not have enough bacteria to break down the organic matter effectively.
- Insufficient oxygen: If the compost pile is too dense or compacted, there may not be enough oxygen for beneficial bacteria to survive.
- Lack of a balance of carbon and nitrogen: Compost piles need a balance of carbon-rich “brown” materials (such as leaves and straw) and nitrogen-rich “green” materials (such as grass clippings and vegetable scraps) in order to provide the bacteria with the necessary nutrients to thrive.
- Temperature: Beneficial bacteria thrive at temperatures between 110-160°F (43-71°C) if the pile is too cold, it may not have enough bacteria to break down the organic matter.
To correct this, you can add some finished compost to your pile, this will add beneficial bacteria and help speed up the decomposition process. Additionally, you can make sure that the pile has the right moisture, oxygen, carbon-to-nitrogen ratio and temperature. Regularly turning and aerating the pile, and adding water as necessary, can help ensure that these conditions are met.
25 tips to avoid bad smell from compost
- Keep a balance of brown and green materials in the compost pile, such as dead leaves and branches (brown) and grass clippings and kitchen scraps (green), to prevent unpleasant odors.
- Keep the compost pile moist but not too wet, to prevent the build-up of bad-smelling gases.
- Turn the pile regularly to aerate it and ensure that all of the materials are getting the proper amount of oxygen.
- Avoid adding meat, dairy, and oily materials to the compost pile, as they can attract pests and produce bad smells.
- Use odor-absorbing materials such as activated charcoal, coffee grounds, or wood chips to neutralize any bad smells in the pile.
- Keep a lid or tarp over the pile to keep out rain and contain odors.
- Keep the compost pile in a well-ventilated area, with good airflow to help reduce odors.
- Mix in dry leaves, straw, or sawdust to the pile to absorb excess moisture and prevent the pile from becoming too wet.
- Use a compost accelerator or activator to speed up the decomposition process, which can help reduce odors.
- Be sure to regularly add new materials to the compost pile, and remove any finished compost, so the pile doesn’t become overfull and start to produce bad odors.
- Make sure the compost pile has the correct ratio of carbon to nitrogen, which is important for the decomposition process and can prevent bad smells.
- Chop or shred materials before adding them to the compost pile, as this will help them break down more quickly and reduce odors.
- Keep the compost pile at the correct temperature, as too high or too low temperatures can slow down the decomposition process and lead to odors.
- Use a compost thermometer to monitor the temperature of the pile.
- Avoid adding diseased plants or weeds to the compost pile, as they can spread disease and produce bad smells.
- Use a compost sifter to remove any large chunks of unbroken down material, which can produce bad odors.
- Avoid overloading the compost pile with too many materials at once, as this can lead to bad odors.
- Use a compost turner to help mix the pile and aerate it, which can reduce odors.
- Add a layer of soil or finished compost on top of the pile to help with the decomposition process and reduce odors.
- Keep the compost pile away from any sources of strong odors, such as garbage or sewage, as this can cause the pile to smell.
- Use a compost moisture meter to check the moisture levels of the pile and adjust as needed to prevent bad odors.
- Add a sprinkle of baking soda to the pile to help neutralize any bad odors.
- Use a compost aerator to introduce oxygen to the pile and prevent bad smells.
- Use a cover of straw or leaves on top of the pile to keep moisture in and odors out.
- Consider using a composting bin or tumbler, which can help to contain odors and keep the pile contained.