What you can and cannot compost
Things you can compost!
| Materials | Carbon or Nitrogen | Details |
|---|---|---|
| Alfalfa meal and hay | Carbon | Shredding or chopping it up will help it break down quicker |
| Algae, seaweed and lake moss |
Nitrogen
|
Good source of nutrients and minerals. |
| Apple pomace (cider press waste) | Nitrogen | If dried use as a carbon |
| Ashes (wood, not coal) |
Neutral
|
Use only wood ashes since coal ashes can be toxic to plants. Use sparingly as a pest deterant. |
| Beverages, kitchen rinse water |
Neutral
|
Help keep the pile moist, but don’t over do it. |
| Buckwheat straw or hulls | Carbon | Shredding or chopping it up will help it break down quicker |
| Cardboard |
Carbon
|
If you have lots of this, consider recycling it. Otherwise, shred into small pieces in pile. |
| Cat litter (unused!) | Carbon | Ugh..make sure its unused |
| Clover | Nitrogen | Add it for a bit of luck! |
| Cocoa hulls | Carbon | Shredding or chopping it up will help it break down quicker |
| Coffee grounds (and filters) |
Nitrogen
|
Great source of nitrogen and worms love coffee grounds! The filter will break down so add it too! |
| Cornstalks, corn cobs | Carbon | A little tricky, so shred and/or break down and mix well into pile. |
| Cotton Bur | Nitrogen | Great to use to jump start your pile or warm it up |
| Cowpeas | Nitrogen | Add them if you got them! |
| Dog food |
Nitrogen
|
Best if not a meat based dog food |
| Dryer lint |
Carbon
|
Yum, lint. Make sure you moisten it a little before you add it. |
| Eelgrass | Nitrogen | If dry use as a carbon |
| Egg shells |
Neutral
|
These break down slowly, so make sure to crush these before adding. |
| Feathers |
Nitrogen
|
Slow to break down, shred if possible to speed up process |
| Flowers | Nitrogen | Green use as Nitrogen, dried use as carbon |
| Fruit peels (not limes) | Nitrogen | Best if you cut them up to small pieces |
| Grape pomace (winery waste) | Carbon | When dried and shredded best used as a carbon |
| Green Grass clippings |
Nitrogen
|
When green can be used as a Nitrogen |
| Dried Grass clippings |
Carbon
|
Make sure they are not too wet and mix with dry leaves for best results. |
| Hair |
Nitrogen
|
Good source of nitrogen. Make sure you scatter, so it doesn’t clump. |
| Hay |
Nitrogen
|
The best kind is hay that is not suitable for livestock and is starting to decay on its own. Make sure it is dry and weathered. |
| Hedge Clippings | Carbon | Shredding or chopping it up will help it break down quicker |
| Hops (brewery waste) | Carbon | When dried and shredded best used as a carbon |
| Kelp (seaweed) | Carbon | Good source of potassium (perfect for growing potatoes!). Use sparingly or sprinkle kelp meal in to get your pile cooking. |
| Leather (leather waste) |
Nitrogen
|
Shredding or chopping it up will help it break down quicker |
| Leaves |
Carbon
|
Shredding or chopping it up will help it break down quicker |
| Manure from herbivores (cow, horse, pig, sheep, chicken, rabbit) |
Nitrogen
|
Best if known to come from a herbivore |
| Newspaper |
Carbon
|
Shredding or chopping will help it break down quicker |
| Nut shells | Carbon | Shredding or chopping will help it break down quicker |
| Oak leaves |
Carbon
|
Shredding or chopping will help it break down quicker |
| Oat straw | Carbon | Shredding or chopping will help it break down quicker |
| Sawdust and wood shavings |
Carbon
|
Preferably not from kiln-dried wood |
| Paper | Carbon | Shredding will help it break down quicker |
| Peanut hulls | Carbon | Shredding or chopping will help it break down quicker |
| Peat moss | Carbon | Also great to add to your garden soil |
| Pine needles and cones |
Carbon
|
Shredding or chopping will help it break down quicker |
| Tea leaves | Carbon | Best if shredded to help it break down quicker |
| Vegetable peels and scraps | Nitrogen | Kitchen scraps are a great source of nitrogen |
| Vetch | Carbon | From the pea family, yup add it too |
| Weeds |
Carbon
|
Don’t add if your concerned about spreading the seeds |
| Wheat straw | Carbon | Best if shredded to help it break down quicker |
Things you should NOT compost!
|
Materials
|
Carbon or Nitrogen
|
Details |
|---|---|---|
| Ashes (coal or charcoal) |
n/a
|
May contain materials that are toxic to plants. |
| Cat droppings/litter |
n/a
|
These may contain disease organisms and should always be avoided for composting. |
| Colored paper | ||
| Dog droppings |
n/a
|
Same as cats. |
| Lime |
n/a
|
Acidity can kill composting action. |
| Meat, fat, grease, oils, bones |
n/a
|
Do not break down, can coat materials and “preserve” them, can attract pests. |
| Nonbiodegradable materials | ||
| Toxic materials |
Things that MAY be composted, but only with caution and skill
| Materials | C/N | Details |
|---|---|---|
| Bird droppings |
Nitrogen
|
Some bird droppings may contain disease or weed seeds |
| Diseased Plants |
Nitrogen
|
Make sure your pile gets to at least 135 degrees Fahrenheit for a few days to let it “therma kill” the disease |
| Milk, yogurt, cheese |
Neutral
|
May attract pests, so put it in the middle to deep into the pile |
| Weeds |
Nitrogen
|
For best results, dry them out until crunchy, then add them to your compost pile |
| Sod |
Nitrogen
|
Like diseased plants, make sure your pile gets hot enough to make sure the grass doesn’t keep growing in your pile. |
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Hi! I am preparing to do raised bed gardening for the first time ever. I have very little experience with gardening. I want to do a compost pile, but I guess I need to know some things first… I had been collecting all organic fruit and veggie scraps from my kitchen in a big bowl, well, I haven’t established anything to start the actual compost in outdoors, so I set my bowl out on the deck, meantime a critter has been getting into the kitchen scraps on my deck, should I still use the scraps that have been gotten into in a compost pile? Or are they not safe because of what kind of critter it could be??? Also, I had my husband rake a bunch of leaves up out of our yard for me and there were piles that were already decomposing in our yard, I had him dump some of the more wet decomposed leaves into a garden box to start a compost, is that a good thing to do? Or do I not want to use the slimy wet decomposed leaves? Can I just start an opened compost pile like that? By just using leaves and throwing in my kitchen scraps? I also want to know how soon I can use my compost mixture into my gardening, I was hoping to use it this spring when I’m planting? Can I use it that soon or do I have to wait longer? Thanks!
@Jessica, As mentioned on your other post, yes, the scraps are still good, you need to put them in a sealed container or the critters will keep getting into them. No, I would not start my compost pile where I plan to start my garden unless I think it will be done before I plan to plant. I suggest making a pile on the side, make sure you turn it once a week, keep it moist and a balance of 70% browns and 30% greens. I doubt it will be ready by spring though.
Also, what kinds of liquids can I add to the garden/compost besides water and “compost tea” for instance is 100% fruit/vegetable juice ok?
@Sharon, Adding a minimal amount of liquids like fruit/veggie juice will not harm your compost pile, however I would not get carried away, the acid may kill some of the micro organism which break down the material.
Hi! I am not quite ready to compost yet, but would like to save some of our scraps (fruit and veggie peels). Is it okay to freeze these scraps and then add them to the pile when we are ready?
@Lisa, Yes, you can freeze your kitchen scraps until its time to put them out in your compost bin.
specifically, can fish be safely added to compost heaps.
Many thanks
@frik van der linden, Yes, you can compost fish, however its likely you will attract other animals so most people don’t. Also, your compost needs to get fairly hot, around 120 to 140 degrees to break down the bones, and it will take longer than normal.
A quick zap in the blender or food processer will help a ton when composting fish material, and adding some fish “juice” to your compost bin or pile will add a ton of benefit. Just dont go overboard too much
I have a compost bin from an unused container. It’s white, I’ve noticed that some compost bins at the stores are black or green. Should I spray paint my container?
@Rick, No, I would not bother. Black becomes hotter and that is what you are aiming for but not sure it’s worth the trouble. It would not cause to much a problem to paint but more than likely it will wear off in a year or two.
hi Im about to start my own compost as I have been growing all my own vegies. I would like too know how long should I leave the compost before adding to garden beds.
@Cheryl, I keep my composter going until it looks like dirt, others will only wait for it to break down 60 to 75 %. Typically I let mine break down 4 to 6 months.
I have started a compost pile. It is just a bunch of rocks stacked in a ‘U-shape”. Do I need to cover it with black plastic or will it get ‘hot’ without it.
Renee, Yes you can cover it with black plastic, it will likely help increase the heat and keep the heat in. Make sure it still gets oxygen though and kept moist.
Hi,
I have a big covered 5 gallon bucket that I put food scraps, coffee grounds, etc. in and then I take it to my boyfriends farm and throw it in his big compost pile. I recently went on vacation and when I got back the scraps were a little moldy in the bucket, is it still okay to put the moldy food in the compost pile?
Thanks!
@Jenn
It’s fine. Getting moldy is all part of the decomposition process anyway, so it’s no big deal.
Would the compost pile benefit from outdated vitamins or perhaps a “tea” made from them?
@Karen, I doubt it will be a noticeable benefit to add outdated vitamins but it will not hurt either. Yes I would dissolve them first, just to be safe, so a child does not see them and think they are candy.
I’m wondering about the rhythm of things. Each night, I’m collecting my vegie scraps, but once I put my compost (aluminum trash can) together, then I don’t keep adding, right? Because otherwise I’m not giving it a chance to break down? So what do I do with all my scraps while I’m waiting for my ‘can to cook’? I always imagined composting meant just throwing stuff in a pile as you go… I know there are no hard and fast rules, but could use a couple example scenarios to help get my head in a starting rhythm. I’m a thankin’ ye.
@Sahari, You can batch compost, which means you fill it up and let it finish or you can add as you go and once it’s full then you stop adding. With both you will find a second composter is handy this way you have another bin to add material to once the first is full. If you are using a trash can make sure you add air holes on the sides and drainage hole in the bottom. Mix it once a week and make sure you have it moist as a will wrung out sponge.
What about composting bread? I’ve read a lot of conflicting information about it.
@Jessi, Composting bread is not normally recommended because it can bring it maggots, worms or mold, however some people don’t mind that.
I have just bought a compost bin so I can cut down on waste and to save money on gardening, I have the bin sitting under a bushy tree it has an open bottom and a sliding door at the bottom to take the compost out when its ready. My Questions are, do i need to mix the material on a regular basis and do i need to add moisture or will it get the moister from the ground because of the open bottom? is it a bad place to have it because it is shaded from the sun light? thank you
@Pol, You should try to mix or aerate your compost a few times a month and once a week if possible. Also keep it as moist as a well wrung out sponge. If you can move the compost bin over to a sunny spot it will help but not the end of the world if it’s in the shade or partial sun.
Thank you very much for all this ideas. I already started my compose, I think that I need to mix everything. I’m using a black, plastic garbage can. No bad smell or flies around and again thank you very much.
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