Compost Smells Like Poop or Manure? Here’s How to Fix It

Making your own compost is not only satisfying but one of the best ways to add nutrients to your garden. However, nothing is more annoying than dealing with compost that smells like poop. Opening that compost bin and having to deal with the stench daily isn’t pleasant.

Compost has a naturally earthy smell but if you notice a sulfur-like aroma wafting from your compost bin, that means that the compost isn’t decomposing correctly. Smelly compost can be due to various issues, which are all addressable and invariably fixable. Read on and I’ll explain why compost smells like poop and the best ways to fix it. 

Reasons Why Your Compost Stinks of Poop

There are a few reasons why your compost could be stinking. Here’s a closer look at what might be causing an unpleasant stench in your compost heap: 

Green and Brown Material Imbalance

When creating compost it’s important to layer green and brown materials. Having a balance of ingredients can help regulate the high nitrogen (green) and low nitrogen/high carbon (brown) materials you are adding to your compost pile.
 

Improper layering can lead to stinky compost, insufficient temperatures, and a slower decomposition process. According to Cornell University, keeping your compost at a ratio of 30:1 browns to greens and adjusting as necessary can help prevent stinky compost. 

Adding in the following greens and browns can promote healthy compost:

Greens (High Nitrogen)Browns (High Carbon)
Grass ClippingsFall Leaves
Vegetable and Fruit ScrapsTwigs/Branches/Pine Needles
EggshellsStraw/Hay
Coffee Grounds/Tea BagsPaper (newspaper, paper plates, napkins)
Animal Manure (no dog or cat)Cardboard (not coated with wax)

It’s important to note that some greens can turn to browns, such as old grass clippings, so you should adjust your compost pile accordingly. 

Wet Compost

Damp compost is pretty normal during spring and fall. But compost with a slimy texture or that’s turning black could indicate an ongoing moisture level that is doing more harm than good.

The problem with wet compost is that it lacks aeration, which is needed to decompose the organic material. Instead of composting, the pile starts rotting. 

Compaction

Compaction occurs when you continue adding compostable materials to the top of a pile and then forget to turn it regularly. This causes the various components to compact together as more and more weight is piled on top. 

As I already mentioned, composting requires oxygen. A compost pile that’s too compact has restricted airflow, which interrupts the decomposition process.

All of the usable oxygen is pushed out when materials are piled tightly together, and this prevents beneficial microbial activity from occurring. The lack of oxygen causes the compost to produce hydrogen sulfide, which smells like rotten eggs.

How To Fix Smelly Compost

Efficient composting requires following some straightforward but specific rules. Here are all the hints, tips, and tricks that I use to help prevent a foul odor in my compost pile, and ways I go about fixing any unwanted whiffs that do emerge.

Mix Greens and Browns

Avoid having too much nitrogen-rich material in a pile. According to the U.S. Environmental Protection Agency, you should have three parts brown to one part green materials. 

Common brown materials include:

  • Dried weeds 
  • Dried leaves 
  • Dried straw 
  • Sawdust
  • Wood chips

You can also use shredded cardboard and newspaper as brown material. The green matter gets smelly with time but adding enough brown material helps to curb this smell.

Turn the Compost Pile

A compacted compost bin can quickly become smelly. You need to turn the compost once or twice a week to prevent this.

Frequently turning the pile adds oxygen, resulting in faster decomposition and less smelly compost. Turning the compost will also ensure you have a good mix of greens and browns, which is essential for any good compost. Start by sticking a shovel or pitchfork in the compost pile to mix it up. 

You can also avoid compacting your pile by gently laying down alternating layers of green and brown matter.

It may seem a little time-consuming but only incorporating small pieces of shredded/chopped plant matter, leaves, and other food scraps increases the amount of air circulation around the composting microorganisms and this minimizes the risk of smelly compost.

This is a job that kids or grandkids can get involved with. My kids used to love getting messy whilst cutting up the veggie peelings, a pile of leaves, and some old egg cartons. It’s a great way to get kids involved with nature and gardening, as well as encourage them to recycle household waste and save money.

Keep the Pile Dry

Moisture is essential for decomposing but having your compost wet for prolonged periods can make it smelly.

If you notice that the compost is becoming slimy, you should add more dry material such as cardboard or dry leaves. Doing so will help to absorb excess moisture and keep the pile dry.

Also, double-check if the compost pile is in the lowest part of the yard. You could be keeping your compost in an area where water collects, making it wet for more extended periods. Move the pile or bin to a dry location. 

During the rainy season, the pile may also get wet. Cover the pile when heavy rain is forecast to keep excess moisture off the stack. If you’re using a tumbler or plastic square bins, ensure that the bottom has adequate drainage.

An enclosed bottom prevents any excess water from draining out of the compost. The bin needs to be part of the ground, whether you’re placing it on soil, concrete, or a tarp. 

Avoid Adding Certain Things Into Your Compost

Avoid items like animal fat, dairy, meat, and oils as these give off a foul smell and attract pests to your composter. These items don’t break down quickly like other organic materials. Instead of composting nicely, they rot away and can leave behind a stinky odor. 

Balance the Moisture Content in Your Compost

Having compost that is too dry can also be a problem. Dry compost slows down the decomposition process, and this can also make it smelly.

If you notice that your compost is too dry, add some moisture by spraying it with a garden hose. Doing this will increase the heat generated and boost bacterial activity to help with decomposition.

Can You Use Smelly Compost?

We all know that a compost heap doesn’t exactly smell like a bed of roses and will always emit an earthy aroma but you should definitely avoid using pungent or foul-smelling compost. 

An excessively smelly compost pile means that the decomposition process hasn’t occurred as it should. You don’t want to use smelly compost as mulch around a seedbed or plants that are intended for human consumption. Also, the compost may not have the nutrients required to support plant growth. 

What Should Compost Smell Like?

Well-balanced and maintained compost has an earthy and light scent. When completely broken down, compost smells like rich, fresh garden soil. It doesn’t smell like rotten eggs or manure. 

Another option is to try a worm composter. This is clean, smells less, and won’t attract flies. It’s also a fun way to get your compost directly from kitchen waste and scraps.

Final Thoughts: Compost Smells Like Poop

Compost should have a neutral earthy smell and not produce a strong odor. Compost that smells like poop or manure is an indication that something is amiss. Too much moisture, a lack of green matter, and not enough aeration can all cause your compost to smell.

Fortunately, just by making a few simple corrections and sticking with a few basics, you can reduce the foul odor and have a healthy source of compost to use in your garden.

If you want to take your composting to the next level, why not learn how to make my 6-step easy compost tea recipe? It’s a great way to make your compost go even further by creating your very own liquid fertilizer.