The Definitive Guide on How to Compost Everything from the Garden and Kitchen

compost bin contents
compost bin contents

Just about everything can be composted using cold (slow) composting, hot (fast) composting, worm farms (vermicomposting), bokashi composting and Hügelkultur composting.

The table in this article lists how to compost just about every garden and kitchen material that can be recycled, and which composting systems can be used to compost it.

One of the most wasteful and unsustainable things to do is to toss out perfectly good organic matter (materials that were once living) from the kitchen or garden. Everything can be composted, provided that the correct method of composting is used!

The Complete List of Garden and Kitchen Waste Materials and How to Compost Them

The table below list almost every compost material in alphabetical order, and shows the methods that can be used to compost it.

Materials marked with a marked with a tick (✔) can be composted using the method indicated.

Materials marked with a cross (✖) in the table should not be composted using the composting method the cross appears under. If all rows are marked this way, the material (which is usually toxic) is not suitable for composting in any way whatsoever!

Any items marked with an asterisk (*) in the table are either usable in small quantities, or there are conditions when using them, which are listed below the table.

MaterialHot CompostCold CompostWorm FarmBokashi Compost
Animal manures, vegetarian
Ash, BBQ briquette
Ash, wood✔ *✔ *
Bamboo skewers
Bread
Brown paper bags
Cardboard, printed
Cardboard, unprinted
Cereals
Cheese
Chopsticks, wooden
     
MaterialHot CompostCold CompostWorm FarmBokashi Compost
Citrus, peel or fruit✔ *✔ *
Coffee grounds
Cooked vegetables, grains, pasta & rice
Cooking oil
Dairy products✔ *
Diseased plants
Dryer lint
Egg cartons
Egg shells, crushed
Fats, and foods containing this
     
MaterialHot CompostCold CompostWorm FarmBokashi Compost
Fish & seafood✔ *
Flour
Flowers, cut
Fruit & vegie scraps
Garden prunings
Garden waste
Garlic
Kitchen scraps, fruits & vegetables
Lawn clippings
Leaves
     
MaterialHot CompostCold CompostWorm FarmBokashi Compost
Meat, or foods containing this✔ *
Natural fibre fabrics
Newspaper✔ *✔ *
Onions✔ *✔ *
Paper, bleached
(eg. office paper)
Paper, glossy, coated
(eg. magazines)
Paper unbleached non-glossy
Personal hygiene products
(tissues, tampons, etc)
Pet hair and feathers
Pet poo from non-vegetarian animals
(dogs, cats, etc)
     
MaterialHot CompostCold CompostWorm FarmBokashi Compost
Pine needles
Plants treated with toxic pesticides, herbicides
Rice
Sales receipts & thermal paper
Sawdust✔ *✔ *
Sticky labels
Straw mulches
Tea bags✔ *✔ *✔ *✔ *
Toothpicks
Vacuum cleaner dust
     
MaterialHot CompostCold CompostWorm FarmBokashi Compost
Weeds that regrow from cuttings, seeds, roots
Wood ashes
Wood shavings
Wood, treated
(pieces or sawdust)
Woody branches large
Woody branches, mulched

Composting materials marked with an asterisk (*) have certain conditions when used, and these are listed below in alphabetical order:

* What You Should Not Put in Your Hot or Cold Compost

  1. Ash from barbecue briquettes or coal – these are not the same as wood ash, and contain toxic chemicals
  2. Ash from wood (wood ash) – can be added to compost, or directly to garden beds, in small quantities, more frequently. Don’t add too much all at once as it’s very alkaline, will raise pH and can stop composting process.
  3. Branches (large) – take too long to break down unless they are mulched first, use the technique of Hügelkultur to compost large branches and tree trunks
  4. Citrus peel – can use in very small amounts, too much and they can kill the compost bacteria
  5. Cooking oil – will become rancid and smell unpleasant
  6. Dairy products – will rot, smell unpleasant and attract pests such as rodents
  7. Dryer lint – once recommended, but now contain too many synthetic fibres which don’t break down
  8. Fats, or foods containing these – will rot, smell unpleasant and attract pests such as rodents. Can be hot composted when placed in centre of pile when first constructed.
  9. Fish scraps, or foods containing these – will rot, smell unpleasant and attract pests such as rodents. Can be hot composted when placed in centre of pile when first constructed.
  10. Labels (sticky), such as those on produce and packaging – are made of plastic and/or contain toxic chemicals in the glue
  11. Meat scraps, or foods containing these – will rot, smell unpleasant and attract pests such as rodents. Can be hot composted when placed in centre of pile when first constructed.
  12. Onions – can use in very small amounts, too much and they can kill the compost bacteria
  13. Paper (bleached), eg. office paper – contain toxic chlorine-based chemicals which shouldn’t be composted
  14. Paper (glossy or coated), eg. magazines – contain toxic chemicals
  15. Paper (thermal) and sales receiptscontain a mix of toxic chemicals which shouldn’t be composted
  16. Personal hygiene products, such as tissues, tampons – unhygienic, health hazard
  17. Pet poo from non-vegetarian animals, such as cats, dogs and other meat-eating animals – contain many pathogens which are a health hazard and can cause diseases
  18. Plants (diseased), should be disposed of in regular landfill garbage bin or burnt – can cause diseases to spread in the garden)
  19. Plants treated with toxic pesticides and herbicides – will contaminate compost, soil and food with toxic chemicals, some herbicides don’t break down and will contaminate compost
  20. Tea bags (plastic mesh) – some tea bags are made of a fine plastic mesh rather than the traditional paper bag, the plastic does not break down
  21. Vacuum cleaner dust – once recommended, but now contain too many synthetic fibres which don’t break down
  22. Weeds which regrow from cuttings, seeds or roots
  23. Wood (chemically treated) pieces or sawdust, such as CCA (copper-chromium-arsenic) treated pine – contain highly toxic copper, chromium and arsenic which will contaminate soil

* What You Can Put in Your Worm Farm (With Caution!)

  • Citrus – use only small amounts, or none at all
  • Onions – use only small amounts, or none at all
  • Vacuum cleaner dust – only if carpets are made of natural fibre, not synthetic carpets

* What You Should Not Put in Your Worm Farm

  • Fish – will rot, smell unpleasant and attract pests such as rodents, use a Bokashi bin instead to compost meat
  • Garden waste – too slow to break down in a worm farm, use regular cold composting or hot composting instead.
  • Manures (fresh) – many animals are treated for worms with vermicides, which pass into the fresh manure and will kill your worms, compost manures from vegetarian animals such as cow, horse, sheep for three months first!
  • Meat – will rot, smell unpleasant and attract pests such as rodents, use a Bokashi bin instead to compost meat
  • Paper (bleached), eg. office paper – contain toxic chlorine-based chemicals which shouldn’t be composted
  • Paper (glossy or coated), eg. magazines – contain toxic chemicals
  • Paper (thermal) and sales receiptscontain a mix of toxic chemicals which shouldn’t be composted
  • Pet waste – from meat-eating animals such as cats and dogs, was once only used in a dedicated worm farm for pet waste only, but most pets are now treated for worms with vermicides, which pass into the pet poo and kill the worm. Use a dedicated, in-ground pet poo bokashi system, which can be purchased for this purpose.
  • Tea bags (plastic mesh) – some tea bags are made of a fine plastic mesh rather than the traditional paper bag, the plastic does not break down

I have also made this information available as colourful infographics below, there are six separate images which can be saved and are printable:

table of compost materials how to compost everything from garden and kitchen
table of compost materials how to compost everything from garden and kitchen
table of compost materials how to compost everything from garden and kitchen
table of compost materials how to compost everything from garden and kitchen
table of compost materials how to compost everything from garden and kitchen
table of compost materials how to compost everything from garden and kitchen

More detailed information on each of these systems of composting is available in the following articles:

7 Comments

  1. Jon says:

    Brilliant – thanks Angelo – this is very helpful indeed – I didn’t realise about the office paper. The other question I have is about purchased food, which would contain additives. Can this be composted?

    1. Angelo (admin) says:

      You’re welcome! The only foods that can’t be composted by some means or another are highly processes food filled with artificial preservatives, these are chemicals which stop bacteria breaking down the food!

  2. Maria says:

    Hello Angelo, just wondering about the recommendation to not use egg cartons in a worm farm. I use a non-bleached carton with no print to cover the top tray. Is this bad for my worm farm?

    1. Angelo (admin) says:

      Hi Maria, I use non-bleached egg cartons in my compost, and I tear off the part with the label and put that in the recycle bin instead. The possible problem with using them in a worm farm is that they might take a bit too long to break down, since they’re a carbon-rich material like newspaper, but much denser. The simple rule I use for worm farms is that they’re for processing safe materials that break down very quickly.

      1. Maria says:

        Many thanks for the clarification!

  3. Jon says:

    Hi Angelo – you’ve got tea bags as OK to compost. I’ve read that most of them contain plastic. Just wondering on your thoughts please.

    1. Angelo (admin) says:

      Hi Jon, tea bags were traditionally made of paper, and were fine to compost. The new teabags, especially in non-organic teas, are made of a fine plastic mesh, which don’t break down, and can’t be composted. I’ll add an update on the page, thanks!

Leave a Reply to Jon Cancel reply