13 Things You Can’t Compost | What Not to Compost

Do you know what not to compost? You can compost almost any item but there are 13 things you can’t compost. Find out!

things you can't compost

Composting is a great way to make your own organic fertilizer it allows you to decompose the waste material of your garden and food scraps of your home, which otherwise would have been thrown into the trash. Meanwhile, you can compost almost anything that is organic and was once living but there are some things you can’t compost or you should avoid composting them in large extent to avoid hassle. So what are these? Find out what not to compost in this list.

What Not To Compost?

1. Inorganic and Non-Biodegradable Materials

Inorganic and non-biodegradable materials like plastic, glass, aluminium foil, metal should never be thrown into a compost pile because it will never break down. Also, pressure treated lumber must be avoided too as it’s treated with chemicals.

2. Coated or Glossy Printed Papers

Don’t compost magazines, catalogs, old business cards or cards and wrapping paper or papers with the glossy appearance. As chemicals and toxic substance in them can be damaging for your plants later. However, you can compost newspapers, textbook pages or papers with less or no ink.

3. Diseased and Infested Plants

Residues of diseased plants or plants that are infested by garden pests must not come in the with the compost pile.

4. Bakery Products

Products such as cakes and pastries attract pests, insects and animals. However, you can compost slices of bread or pasta but do remember when you put any food scrap in the compost pile, bury it deep so that it will not invite unwanted beings.

5. Feces and Manure of Carnivorous Animals

Meanwhile, poop and manure of vegetarian animals like chicken, goat, cow, horse and rabbit is beneficial for your plants. On the contrary, the litter of your dogs and cats or other carnivorous animals or human feces must not be thrown into the compost heap because this can carry pathogens and parasites that transmit infectious diseases and harmful to human.

6. Cooking Oil

There are reasons why you should not add cooking oil to your compost pile. First of all, it can slow down the composting process. Also, it has a smell that can catch the attention of animals and insects. It is found that cooking oil can alter the moisture level of the compost too.

7. Meat Products

Leftover meat and animal fats should be avoided in the compost pile. They decompose very slowly and stink a lot. Moreover, they also attract rats, racoons, cats and stray dogs. Annoying insects like flies, maggots etc. may buzz over them too.

8. Dairy Products

Avoid composting dairy products like milk, cheese, and butter if you don’t want to invite pests and rodents.

9. Personal Hygiene Products

Tampons, sanitary towels, diapers, tissue papers, stained materials with human blood or other personal hygiene products can propose a health risk and must be avoided.

10. Sawdust

You can compost sawdust as it soaks excess moisture in wet compost heaps but sawdust that comes from treated wood needs to be avoided. Also, you should include it in the layers of compost, you just have to take into account that it is important to put it in small quantities.

11. Weeds

The word weed is enough to tell you why you should not compost it. Instead of breaking down, it is possible that their roots may set down and plants will regrow again in the heap. Also, if you add their seeds they will germinate again whenever you’ll amalgamate compost to the soil.

12. Tomatoes

There is no problem in composting tomatoes. However, you should avoid composting tomato fruits unless you want baby tomato plants sprouting everywhere in your garden when you’ll use that compost.

13. Plants treated with Pesticides and Herbicides

Never put plants or grass clippings of the lawn treated with pesticides or herbicides.

A Few More Things to Avoid

There are certain things that must not be added or added in very small amounts to the compost, such as black walnuts because they contain a chemical called juglone, which can be toxic to some plants such as tomatoes and inhibit their growth. Also, when you add fruits in your compost pile, fruit flies will feed on them, to avoid this problem never leave them exposed or open above the heap.

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Do you know what not to compost? You can compost almost any item but there are 13 things you can't compost. Find out!


  1. Hi composting made easy is interesting. I live in Lahore, Pakistan and am interested in growing organic vegs in soda bottles (1.5 ltr). I need to make my own pesticides. I am inexperienced and need help. I want to know what vegs can be grown in Lahore.

  2. As I am learning more and more about gardening in general (I am a newbie), I haven’t given much thought to things that I shouldn’t compost. Thanks for sharing. This list will come in handy.

    • I am not an expert. We have had a compose pie for years though. As long as your burning none treated materials then yes. Wood ash is great.

    • Hi!

      Pine needles are a fantastic source of “browns” (carbon) to add to your compost.
      I live in an area where pines are abundant and I constantly use their leaves in my compost piles.
      Roughly, for every part of kitchen waste or “greens” (nitrogen), you’ve to add one part of pine needles (carbon).

      Wonderful article, thank you!

  3. great site, can i put cinnamon powder in my composite bin. i have about 1.5 kilos of it. ive gone onto the organic cinnamon so my non organic is for the bin.


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