The following are the EPA’s lists on what you should and shouldn’t compost.

What to compost:

  • Fruits and vegetables
  • Eggshells
  • Coffee grounds and filters
  • Tea bags
  • Nut shells
  • Shredded newspaper
  • Cardboard
  • Paper
  • Yard trimmings
  • Grass clippings
  • Houseplants
  • Hay and straw
  • Leaves
  • Sawdust
  • Wood chips
  • Cotton and Wool Rags
  • Dryer and vacuum cleaner lint
  • Hair and fur
  • Fireplace ashes

What not to compost and why:

  • Black walnut tree leaves or twigs
    – Releases substances that might be harmful to plants
  • Coal or charcoal ash
    – Might contain substances harmful to plants
  • Dairy products (e.g., butter, milk, sour cream, yogurt) and eggs*
    – Create odor problems and attract pests such as rodents and flies
  • Diseased or insect-ridden plants
    – Diseases or insects might survive and be transferred back to other plants
  • Fats, grease, lard, or oils*
    – Create odor problems and attract pests such as rodents and flies
  • Meat or fish bones and scraps*
    – Create odor problems and attract pests such as rodents and flies
  • Pet wastes (e.g., dog or cat feces, soiled cat litter)*
    – Might contain parasites, bacteria, germs, pathogens, and viruses harmful to humans
  • Yard trimmings treated with chemical pesticides
    – Might kill beneficial composting organisms

https://www.epa.gove/recycle/composting-home, 2019