5 Common Reasons Compost Smells Bad (How to Stop It)

A compost pile in the garden can be wonderful, but a compost pile can occasionally smell bad.

This leads us and many other people to wonder, “why compost smells bad?” and some common reasons why it smells bad when the compost breaking down in your garden.

When your compost smells bad, it’s often an indication that your balance in your compost pile is not even. It’s often because there is too many greens, too much moisture, or either too little aeration. All these things or a mix can cause a compost pile to smell very bad in your garden.


Does a great mixture of compost smell bad?

A great mixture and balanced compost pile should not smell bad. A balanced compost pile will smell fresh and more like dirt. If it doesn’t, there is something wrong and your compost pile seems to not heating correctly up and be able to break down the organic material.

There is only one exception for that your compost smells bad and that is if you are composting manure in your compost pile in your garden, which is not that often seen in private homes, but normal for farmers. Composting manure in a compost pile will commonly smell until the manure breaks down the materials.

However, if you are a farmer or in another way have to compost manure, you can suppress the smell a lot by cover the pile with straws, leaves, or even newspapers of a height of 6-12 inches. By covering compost manure you will reduce the smell considerably.

1) Wet, soggy and slimy

Nothing is more frustrating than slimy and cold compost. But how does it even get cold and too slimy?

There are usually three factors that can be associated with getting slimy compost. Poor aeration in the compost, too much moisture, or even not enough nitrogen-rich material in the compost pile.

A compost pile with too many materials that will mat down, when it will get wet such as grass clipping and hay can become so dense, that the center in the compost pile doesn’t receive any air.

If there is no air in your compost pile and you leave a suffocating heap uncovered in the rain for a certain time, you’ll end up with cold and slimy compost.


Since aerobic bacteria can’t live in a poor oxygon environment it’s a lot better to choose anaerobic bacteria, because they don’t require air to thrive in.

Those small microbes are essential for creating great compost, but for anaerobic bacteria, it will take a lot more time to compare to aerobic bacteria, because anaerobic bacteria will slow down the process and the compost will usually be soggy and slimy during the long process of generally 2-3 years.

Soggy and slimy compost is fortunately easy to fix. If it’s raining a lot in your area and wet weather is a huge part of the problem, it’s a great solution to place a tarp over the compost pile.

However, you can also add some non-matting ingredients such as sawdust or shredded corn cobs to help get your pile heating up and fix the soggy and slimy compost.

Your compost pile will heat up within a few days after the non-matting ingredients have been added and afterward you can keep it cooking going forward by turning the pile every week or two.

2) Dry and dusty

It’s quite common to expect dust and dryness during the time from May to October in areas where there is almost nonexistent rainfall during this period.

If this is the case you will see that no matter what materials you pile up in your stack it will not be enough moisture to get the process going.

The bacterial life will not thrive in those environments which will keep stopping the process of breaking down the materials due to its not moisture.

It’s luckily easy to fix and you’ll find the solution down below.


Water is the simple solution here! Your compost ingredients in your pile should feel about as wet as a damp sponge.

Turning around the ingredients and watering your dormant pile will help it bring it to life quickly. However, if it doesn’t heat up, it’s often a sign that it might lack of nitrogen-rich materials such as corncobs, fruit pits, etc.

Remember to not let the compost pile dry out again once the pile starts cooking. When the tiny microorganisms start to multiply in the process of breaking down the ingredients they will use a lot of water.

You may experience that you have to water your compost almost as often as when you water your flowers in your garden to not let the compost dry out again.

3) Bugs

It’s common to find both pill bugs and sow bugs in your compost. However sow bugs will not harm your compost at all, but just help to break it down.

However, it is really important that you remove those sow bugs from the finished mixture before you spread it out in your garden because they will often snip off the emerging roots and leaves of your seedlings.

You will often see ants and earwigs also invade your compost pile – exactly like pill- and sowbugs.

Ants and earwigs also invade compost piles. Like sow bugs and pill bugs, they are essentially harmless to the composting process, but their presence may indicate that your pile is on a slow track to decomposition.


The easiest way to get rid of those bugs and out of your compost is to raise the temperature to above 120 F of the compost pile.

To get these bugs out of your compost, raise the heap’s temperature to above 120°F. If you aren’t sure what your compost pile’s temperature is, you can easily use a regular thermometer used for meat if you just wrap it into plastic before you check the temperature.

When the temperature has been raised you can turn the pile over and start to rebuild it and remember to water it frequently. If your pile contains a lot of leaves or grass, you have to mix in a nitrogen source like shellfish shells or corncobs.

The compost pile will start heating and those bugs will depart for a more comfortable place to thrive in. However, to keep the compost pile cooking you have to turn it in every 1-2 weeks.

4) Plants growing

Sometimes you will see that not even a hot cooking compost pile is enough to kill all the seeds it contains. It will usually be weed seeds, but you will sometimes see volunteer vegetables as well such as tomatoes, potatoes, and pumpkins to sprout.


If the compost pile only contains weeds, it’s not the biggest problem, cause you can just pull them up and throw them back into your unfinished compost.

However, if it’s plants, you can of course take those out of your compost pile and plant them in your vegetable garden or somewhere else in your garden.

5) Animals eating my compost

Some might think that raccoons, rats, and skunks eat compost, but actually, they do not eat the compost. Instead, they will just tear up the compost pile to see if there is any fresh edible kitchen garbage they can find and eat.

Both vegetables and any added “forbidden” meat scraps that you have recently buried and added to your compost pile will be interesting for those animals.



By mixing the kitchen garbage with either soil or wood ashes before you add it to the compost pile it can often discourage animals from trying to reach the hidden goods in the hot center of your pile.

It’s a great start and has helped a lot of people with this problem.

However, once those animals have gotten used to visiting your compost pile for a free meal, the best solution is to either build or buy a covered bin, to keep the garbage hunters away.