Can You Compost Oil?

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Quick Answer: Can You Compost Oil?

The answer is complicated. You can compost small amounts of vegetable oil from a normal household. You may add them to a hot compost pile to decompose them. Keep them stirring to prevent the foul smell and keep them covered. Do not add large amounts of oil to the compost pile as they may attract pests and slow down the decomposition process. Large amounts of used vegetable oil can be recycled.

In this guide, I will discuss if its all right to compost oil, and if yes, how to do it.

Read further to know more!

Can You Compost Oil?

The answer is complicated. You may compost a small amount of vegetable oil from a normal household as it is organic. It will take a longer time to decompose. But, EPA warns against using large amounts of grease and oil in the compost pile as they attract animal pests and also inhibit the biochemical processes necessary for successful composting.

Also, do not add oils that have come in contact with meat, dairy, or seafood during cooking. Do not add synthetic oils, gravy, lard, bacon grease, oil from canned fish, and leftover sauces.

The paper towels and cardboard soaked in some oil can be composted. Make sure the compost pile is hot between 120 and 150oF. Also, spread them around the compost and keep them stirring around regularly.

How To Compost Oil With Ease?

You may compost vegetable oils that have not come into contact with meat or dairy-based products. Add only very small amounts at a time and mix them well.

The different steps in composting oil are as follows:

  • Toss the cooking oil– You may add a small amount of canola, coconut, corn, olive, grapeseed, safflower, soy, sunflower, and vegetable oil to the compost pile. Do not add oil that has come in contact with the meat. Spread them throughout the pile.
  • Add green and brown ingredients– Add alternating layers of green and brown ingredients. Keep turning the pile. This will eliminate the odors and prevent the compost from attracting pests.

What Are The Problems With Composting Oil?

The compost pile has problems in breaking down the fat, including grease, oil, and animal fat. They may coat the fibers of certain materials, form water-resistant barriers, reduce airflow, and displace water. This may slow down the decomposition process creating anaerobic conditions and ultimately threatening to kill the compost.

Also, they turn rancid due to a lack of oxygen and poor circulation. This will increase the likelihood of midnight vermins and pests rooting through your compost pile.

Can I Compost Cooking Oil?

Many experts and composting books advise against composting cooking oils but a few oils can be composted in small amounts. The potential problems of adding cooking oils to a compost heap outweigh the benefits of adding cooking oils.

The vegetable oils, including rapeseed oil, sunflower oil, corn oil, or olive oil can be composted in small quantities.

They shouldn’t have come into contact with meat, cheese, or fish as composting them will attract rodents.

It may be ok to add a paper towel soaked in a bit of oil. But, do not pour large quantities of deep-fried oil into the compost bin.


Can you flush oil into the drain?

No, do not flush small amounts of oil down the drain. They may cause a clog and block the drain. You may put it in sealed plastic or metal container and dispose of it in the trash. If you have to dispose of large quantities of oil, contact your local authorities for recycling them.

How to reuse or recycle cooking oil?

You may reuse the cooking oil or use less. Some may use a small amount of oil for your dog food or roll it in bird seed. Few consider recycling cooking oil as biodiesel. Ask your local authorities to safely dispose of cooking oil.

Can you add used vegetable oil to a worm bin?

Some people prefer to avoid adding used cooking oil to the worm bin as they go rancid when exposed to air. While some don’t mind adding a very small amount of oil to avoid harming the worms. It is okay to add a greasy paper towel used to wipe a cooking pan.

Bottom Line

I hope this guide has provided you with detailed information on composting oil.

You may decide on composting the cooking oil after analyzing the associated caveats. If you have tried any other method of composting oil, do let me know.