What should not go into compost?

My wife and I were discussing potential dangers regarding composting. It was clear that we knew very little we were certain of.  What should not go into a compost pile?

If you have an ideal compost pile, i.e large several cubic meters large and you turn it regularly then inorganic things is the answer to the question anything else would be fine. If like me you have rather erratic piles that do heat up on occasion but are not turned and certainly cannot be trusted to kill any pathogens or weed seeds then the list is a little more extensive.

What goes into mine
All non flowering weeds
all vegetable kitchen scraps, including bulk deposits of fruit mush after jelly/juice making
potato tops/strawberry runners etc
all waste from making vegetables marketable (roots, leaves, eaten bits)
soft pruning
Some unprinted cardboard, generally soiled strawberry/egg cartons
Some grass clippings, we have to many to put them all in, but if they are mixed with leaves they are excelent
waste produce, things that go limp on the stand or come back from market, beyond our needs.
Pee
(when we have chickens their straw bedding goes in)

What doesn't go in
Weeds in flower ( I don't want to spread the seeds around)
Potatoes (they just WILL NOT DIE)
Dog poo (goes in it's own hole)
Any other kitchen scraps (we have dogs that would love to steal any meat/bread etc)
Straw unless chickened (I tried this as browns two years later it's still straw)
Twigs/cabbage stems (these just take to long to break down, they go in their own forgotten piles on top of stumps I want to rot)

The list of what should NOT go into compost is fairly large to be sure. Some things are just to obvious to mention - but I will do anyway :)
To state the obvious, only organic material should go into the compost heap. I say this because my sister for one, seems to think that plastic flower pots and labels will rot down with the compost!
OK so back to organic no-no's
Dog or cat poo and any poo from a carnivore should not go into compost.
Straw is ok in limited amounts to add 'brown content'
Dairy products
Eggs, meat & fish (except the egg shells which are ok)
Any baked food such as break, cakes etc
No cooked foods especially greasy foods.
Glossy mags or colored paper - brown or white plain paper only.
Pig manure (this has to be composted seperately as it can carry dangerous worms pathogens)

The reasons that various materials cannot be used in compost vary, but usually reveolve around the fact that they cannot rot at all, or they can rot but leave behind unwelcome pathogens or worms dangerous to humans.
There is also the fact that certain dairy products can attract vermin or even Bears to your compost heap.
For more info on composting and building a 3-bin composting area check out this post https://planterspost.com/pallet-composting/

For me the no-no list includes:

doesn't break down fast enough:  Avocado pits, peach pits, nut shells, citrus rinds

can inhibit beneficial bacteria/fungus:  also citrus rinds, allelopathic woods such as cedar

may harbor insecticides or fungicides or ick:  cardboard, paper

There are people right here on Permies who compost all of the above in different circumstances.  So it's not like you *can't* compost avocado pits.  I'm just tired of 1 year later still seeing those avocado pits.  And after working in a factory and seeing the giant jugs of insecticide they spray over the cardboard pallets I trust no cardboard unless it has sat outside for a couple of years.  

I ferment all of our kitchen scraps with bokashi before composting. Using this technique I compost meat, bones, cooked food and used cooking grease. I've seen no I'll effects from it. I have a draining barrel where I dump the bokashi fermented stuff and strain off the liquid which gets fed to trees and shrubs or added to a compost  tea if I'm making one. After its drained well it gets mixed with "browns" in the compost bin.

Bones disappear amazingly fast (and they are not being taken away by vermin, I occasionally find nubs and they are super crumbly). Avocado pits turn into this wild clay like substance . the worms and bugs go crazy

I don't do meat, dairy, dog manure (only pet I have) or shiny paper.  All other stuff goes in.  If a little meat, dairy or shiny paper gets in, I don't sweat it.
Mother Earth News has several good articles on how to set up a bin/pile/tumbler/system and what to put in it.
What you are composting in, how much you are going to manage it and what critters will visit is just as important.  
If possums, raccoons, rats or canines are not an issue - then meat/fish could be composted as well.
Good luck.

This is a good question. I've known folks who say anything goes, to others who are really particular.

My compost piles are in my chicken yard, so I ignore some of the precautions, such as no meat and dairy scraps. The chickens polish these off before we leave the yard, so there's none left for rodants. Some things do take longer to decompose, but these are usually tossed back into the new pile because that's easier for me, rather than trying to maintain separate piles. Any kitchen and garden scraps that are edible to our livestock are fed directly to them, instead of going into the compost. My two big no-nos are weeds with seeds and wiregrass (invasive Bermuda grass). Those things never go into the compost.

Everybody has pretty well covered it!  I must add old potting soil and I throw several bags of peat/ manure/wood fiber mix on.  

Have you ever noticed how much bigger and better the compost pile weird pumpkin, squash, potatoes “whatever” are than those you slaved over and planted! ?  My compost pile pumpkins rock!

Leigh Tate wrote: My two big no-nos are weeds with seeds and wiregrass (invasive Bermuda grass). Those things never go into the compost.

What do you do with those things? What does anyone do with those noxious invasive rhizomes? Currently I live in a rental that comes.with bi weekly yard waste that goes to the municipal.compost operation. I throw all my bind weed and Himalayan blackberry cuttings in there. I try to dry stuff on the sidewalk for a few days before hand and I guess I'd just try to do.that before composting.  Maybe burn that kind of stuff after its dried? I did the soaking barrel once buy it was it's whole.own thing that wasn't ideal and its not a good solution for blackberries

s. lowe wrote:

Leigh Tate wrote: My two big no-nos are weeds with seeds and wiregrass (invasive Bermuda grass). Those things never go into the compost.

What do you do with those things? What does anyone do with those noxious invasive rhizomes?

I let the wiregrass dry in the sun and then use it to mulch pathways. As long as I'm sure it's dead! Non-noxious weeds with seeds often end up in their own piles in the chicken yard. The chickens love to scratch through them and so far they seem to take care of it. Noxious weeds such as horse nettle are can be allowed to dry and burned.

Currently I live in a rental that comes.with bi weekly yard waste that goes to the municipal.compost operation. I throw all my bind weed and Himalayan blackberry cuttings in there.

I've thought about doing that, but I worry that my problems will just be ground up and hauled off in somebody else's compost to become their problem too.  

Theoretically(?), a good compost pile is supposed to generate enough heat to kill weed seeds, but I've never been able to accomplish that.