Why do Compost Bins Smell

Why do Compost Bins Smell? Good Composting 

Why do compost bins smell? Is it possible to reduce the smell that emanates from your compost bin? 

Yes! With the right composting practice, you can keep your compost bins from stinking like a decomposing animal. 

While composting is a good gardening practice, a compost pile can very much turn your garden to a smelly yard; something every responsible gardener tries to avoid. Composting is a simple practice that can be as easy as taking out the trash. But it can be a whole lot difficult when the pile begins to stink and is almost impossible to keep the stink down. 

You can compost almost anything that comes out of your kitchen. Leftover vegetables, fruits, food pieces, decomposing food, grass clippings, and any other thing you feel can be used as nutrients for your plants. 

Most of the things we throw into the compost bin or pile will eventually begin to decay after a few days (or weeks). Once decay sets in, the compost pile begins to give off a pungent smell due to the activities of the micro-organism that builds up inside the pile. 

While you can’t stop the activity of the micro-organisms, you can control the amount of stench that comes out of your compost. 

Before I share with you a few good composting practices, let us first take a look at some of the reasons why your compost bin is giving off a strong stench. 

The Compost is Too Compacted

When you pack your compost too tightly, it can make it difficult for air to circulate around the pile. Without enough oxygen in the pile, it becomes difficult for the micro-organisms to perform their function – which is to break down the compost. Without air, the bacteria cannot populate to speed up decomposition. The bacterium that is left in the pile begins to give off a foul smell that results in a smelly backyard or garden. 

You need the microbes to settle properly into the compost pile so you need to ensure they have enough room to stay in. For your compost to be properly ventilated, you will need to ensure that you place it in an area where it can get enough ventilation. Avoid keeping the compost in a shady or damp area. Also, you want to ensure that there is enough space between piles to allow air to circulate. Too much of dense materials on top of each other will make it difficult for air to enter into the heart of things. 

You can use a rake or pitchfork to turn the compost pile regularly to free up things inside the pile. This also helps to expose the bottom of the pile to some fresh air. This helps to reduce the smell when performed regularly. 

Wet Compost Smells the Worst 

When there is too much water in your compost, it can cause the pile to smell. More than when your compost is dry. For your compost to decay properly, it will have to be left outdoors under the sun, rain, and wind. These are three elements that are important for composting to take place. However, when there is an excess of any of the elements, it can affect the procedure negatively. 

Too much water in your compost will make it difficult for the bacteria to get to work, and cause your backyard to smell. To drain excess water from your compost, you will need to keep it in an area where it can get direct access to sunlight. You should make it a habit of turning the compost pile once a week. This can help to circulate air and heat around the pile to keep the stench down. 

Wrong Composting Materials


Another reason why your compost smells so bad is because there are materials in the pile that aren’t supposed to be in there. Materials such as dairy products, meats, animal fat, and oils are not supposed to be a part of your compost pile. 

The best rule to follow when placing materials in your compost pile is to make use of plant-based materials. This can seriously keep your compost bins from smelling. It also keeps dogs, cats, raccoons, and other rodents from sniffing out your compost bin. 

Not Balancing the Greens and Browns 

One of the best composting practices you need to follow to ensure your compost is rich is to use the right ratio of green and brown materials. Green materials are rich in nitrogen and include green leafy vegetables, and grass clippings; while the brown materials are rich in carbon and include straws and shredded newspaper. 

When the green material in your compost is more than the browns, your compost smells like ammonia. This is a sign that you need to include more shredded newspaper, brown leaves, straw, and pine needles, to balance things out. 

Layer your materials evenly, and don’t forget to use a rake to turn the compost once a week to allow for air and heat to get circulated around the pile. 

Lack of Microorganisms

Like we mentioned earlier, your compost needs the right population of microorganisms for breakdown to take place. When the population isn’t enough to support decay, the compost pile won’t heat up and begins to give off a foul stench. 

You can support the growth of microorganisms in your compost by placing the compost bin on the ground. You can also speed things up by introducing organic soil or fresh compost to your bin. This will lead to the speedy formation of microorganisms and leads to a quick decomposition of your compost. 

With the right composting practice, your compost pile shouldn’t smell. This you can encourage by simply 

  • Ensuring that the compost isn’t compacted. 
  • Keep the compost in an area where it can get direct access to sun, rain, and air. 
  • Place your compost bin on the ground.
  • Use the right composting materials.
  • Balance the ratio of green and brown materials in the composting pile. 
  • Use a lid to cover your compost bin when it rains heavily. 

How do you keep your compost from smelling? We will like to hear from you in the comment section.