If your kitchen or outdoor compost bin is producing a bad odor, it can make your living at home very uncomfortable. There are two main reasons why they smell, such as an imbalance of nitrogen to carbon materials within your compost (too much nitrogen and not enough carbon), and the compost being too wet and soggy.
1. Too many nitrogen-rich materials, and not enough carbon-rich materials
A compost pile should have a good mixture of nitrogen-rich materials and carbon-rich materials. If the pile is out of balance and has too much nitrogen, you can get an ammonia smell. Nitrogen-rich materials are things like fresh lawn clippings, coffee grounds, and fruit and vegetable scraps.
You can fix this problem by adding more carbon-rich materials. These are things like dried leaves, straw, dried grass, and general materials that have dried up. This kind of material helps the bad odor go away.
2. Your kitchen or outdoor compost is too wet and soggy
It is fine to have composting materials that are damp, but when it is too wet and soggy, it leads to the production of an odor that smells like ammonia or even vomit sometimes. The best way to immediately help with the smell is by adding more carbon-rich materials to help dry out your pile.
Things like dried leaves and lawn clippings will help, and then you need to cover up the pile or bin when it rains and uncover it in sunny weather until it dries out to the correct moisture level again. Overly wet compost can also benefit from being drained and aerated correctly, and you can also help mask the smell by placing shredded paper or cardboard on top of the pile.
These are the main reasons why a kitchen or outdoor compost bin smell bad and a quick summary of ways on how to make that bad odor go away. Now let’s look at it more deeply so you can understand further:
1. Add Brown Material to the Compost
Composting is a fine balance, and part of this balance is between browns and greens. These are the two different types of organic materials that are either nitrogen rich, or carbon rich.
Greens are high in nitrogen. They help microorganisms grow in the compost pile, and they help make hot temperatures within the pile. These hot temperatures are responsible for killing off a lot of the weed seeds and things that you do not want in your finished compost. Greens provide the juice that gets the composting process going.
Brown materials are high in carbon. They supply food that soil organisms need to survive, and they also act as a filter. If you have a carbon filter for a water jug or a fish tank, you’ll find this easy to remember. The carbon filter in your compost helps it absorb odors, and it also prevents nitrogen from leaching from the pile. With carbon, compost smells less, and it also turns into humus more quickly.
Dried leaves, sawdust, shredded paper, and hay are examples of brown materials. Just add these to the compost, and you will help balance and dry out the mix.
2. Turn or Aerate the Compost
Compost needs air, and there are living things in your compost (which thrive on oxygen). If there is no oxygen, the compost pile will ferment instead of composting aerobically. This then turns the materials in the compost into ammonia and acids, as well as enable the release of methane and carbon gas.
Methane gas is often what you smell when your compost stinks. You need to ensure that the pile gets back to the required aerobic state, through the introduction of oxygen into the pile. This automatically helps the microorganisms, ensuring that they thrive and compost more easily.
Turning the pile is the best way to aerate it, as it brings air into the pile. It also makes material at the sides of the compost pile can move into the center, where it is hot. Aeration ensures that the moisture in the composite reduces.
3. Drain the Compost
What do you get when you combine water and rotting vegetables? Well, it may smell a lot like your compost bin when it stinks. Yes, the finished compost will be moist, but it shouldn’t be foul and wet. Stagnant water can reduce the oxygen levels within the pile. The result is an anaerobic activity, methane gas, and slimy, slippery compost.
Allow for drainage in the pile and make sure that you alternate dry, brown materials with damp, green ones. The most common composting mistake is to add only fruit and vegetables and nothing else, leading to excessive green material and too much moisture in the bin. To drain the compost, you need to punch holes into it, and the best way to do this is with an aerator.
4. Mask the smell
Adding a layer of material to the top of the pile provides a barrier that helps to prevent any smells from escaping the bin. Things like shredded paper, cardboard and hay are ideal for keeping bad odors confined within the bin. For a kitchen composter, it is a good idea to layer the top with some soil before the shredded paper, etc and then move it somewhere outside when it is starting to fill up. The composting process will then carry on outdoors.
If your compost smells, you know what to do, open the bin, and stir. Make sure that the outside of the compost moves towards the inside. Punch holes in the compost with an aerator. Ensure that the compost has drainage available, and most of all, add browns to the mix. Finally, add a nice layer of shredded paper or cardboard on top to help mask the smell. Remember to move your kitchen compost outdoors to finish off the composting process.
Then your kitchen or outdoor compost bin will have far fewer odors, and you’ll have lovely compost that smells like rich, fertile soil just the way it should be. The more you compost, the more you will understand how to keep that nicely balanced and slightly damp happy medium for your scraps to break down without smelling.