Spilling the Compost Tea: Should Compost Have a Smell?
Let’s spill the compost tea…should compost have a smell? Short answer: yes. A healthy compost pile will have an earthy scent, but bad odors could signify a problem with the composting process and attract unwelcome pests.
The two most common causes of bad-smelling compost are are:
1. Imbalance of “green” and “brown”: your pile is too high in nitrogen-rich materials like food scraps and is missing carbon-rich materials
2. Not enough oxygen: anaerobic conditions within the pile will cause food to rot and emit an unpleasant smell
Now that your compost has alerted you of this imbalance, we will walk you through how to fix it.
Increase your browns
“Browns” are materials relatively high in carbon such as dried leaves, wood chips and shavings, straw, shredded newspaper, and woody yard and garden trimmings. Browns are key to the microbes’ balanced diet as they provide the energy needed to metabolize proteins and other nitrogenous compounds.
Rebuild the pile and add more browns, especially bulky materials such as wood chips. These allow for more airflow through the pile, absorb excess moisture, and balance nitrogen levels. Start with a ratio of 2 parts brown to 1 part green. This can vary depending on the type of brown material used. Brown leaves, for example, break down more quickly than coarser brown material such as wood chips, so adjust your ratio as needed.
2. Add oxygen
Maintaining an aerobic (i.e. oxygen-rich) environment helps to avoid unpleasant odors that often arise due to anaerobic (i.e. without oxygen) composting conditions. Turn the pile to increase oxygen levels, and increase turning frequency to minimize anaerobic pockets in your pile.
A smelly pile can attract animal visitors, so make sure to keep up with your maintenance! Also avoid leaving food scraps exposed to keep your pile pest-free.
You got this! A little attention goes a long way toward keeping your compost (and your nose) happy. 💪🍂
If you’re interested in learning more about how to build a healthy composting system, check out this video workshop from LA Compost to learn the compost basics.