What You Can Compost: From Everyday Items To The Bizarre...

Hair. Dead chickens. Fish. I’ve composted them all.

In fact, if your pile or bin maintains a temperature of at least 130-160°F (55-70°C), you can compost almost anything that’s recently been alive. Even if it’s not hot, you might be surprised at the number of things you can turn into compost.

From garden waste to household scraps, and even materials found on a countryside stroll or a trip to the beach, there’s no shortage of possibilities for enriching your compost heap. The diversity of materials ensures you’ll always have something to add, whether it’s nitrogen-rich greens or carbon-heavy browns.

So in this post, we’ll cover:

Which materials are more challenging, and should only be composted under ideal conditions
The different materials that can be composted, along with tips on how to deal with them

List of compost materials

Looking for a specific material? Start with the table below. If you’re looking for specific composting tips for a material, scroll down further or use the table of contents above.

Material	Note*	Difficulty**
Alcohol	Green	1
Blood meal	Green	1
Bones	Green	4
Coffee	Green	1
Cooked food	Green	5
Dairy products	Green	5
Egg/oyster/clam/crab shells	Brown	2
Fish	Green	5
Grass Clippings	Green	2
Green Manure	Green	1
Hair	Green	3
Leaves	Brown	2
Manure	Usually green.	1
Manure from carnivores	Green	5
Meat	Green	5
Newspaper and cardboard	Brown	2
Seaweed	Depends on type.	2
Shredded paper	Brown	2
Soil	Brown (use sparingly)	1
Tea	Green	1
Urine	Green	1
Weed seeds	Green	4
Weeds	Green (but can be balanced if mixed with soil)	1
Wood ash	Brown	1
Woody plants	Brown	2

*Green means high in nitrogen, Brown means high in carbon. Layer green and browns for the best results.

**1 = Easy: Requires minimal effort (e.g., vegetable scraps, coffee grounds). 5 = Difficult: Needs special conditions or may carry risks (e.g., meat, which can attract pests).

From the garden

Grass clippings

The combination of a nitrogen high green and the small size of cut grass means it gets hot fast. On its own, though, the high moisture content means it tends to go into a sticky mess.

Grass is best mixed with a brown to achieve a better carbon:nitrogen ratio and to soak up some of that moisture.

Weeds and excess plants

Weeds pulled from your soil often make a great material for the compost pile, as they come with a bit of carbon rich soil that balances out the nitrogen.

Most weeds won’t regrow after being composted – even if hot temperatures don’t kill them, the lack of light will. However, weed seeds, if not composted at a high temperature, are likely to survive.

If you pull them out fast when they’re young, this doesn’t matter too much – if not, it may be worth removing them from the mix.

Woody plants

Sticks and woody plants are harder for compost bacteria to digest, and can take longer to compost. They do have their uses, though.

Sticks placed at the bottom of the compost pile creates free air spaces which help provide oxygen to bacteria. Smaller pieces of wood, especially when dry, can help also help create room for oxygen in the compost pile.

Woody plants, sticks and the like can be composted more quickly when broken up. If you have large quantities of woody material, it may be worth investing in a compost shredder or chipper.

Larger pieces of wood can also be composted under the soil in a system known as Hügelkultur.

Leaves

Leaves can be gathered and composted on their own – leaf mold makes fantastic compost. At full size, this can take a couple of years, so again they may be worth shredding.

Leaves can be shredded with a lawnmower. When combined with grass they can make a fantastic composting material, with the carbon from the leaves offsetting the nitrogen from the grass.

Learn more: Leaf Mold Magic – How to Use Fallen Leaves to Improve Your Garden Soil

Green Manure

Green manure is plant material that is grown to enrich the soil. Different green manures achieve different things. For example, legumes will fix nitrogen from the air while alfalfa will draw minerals up from deep in the soil.

Field beans growing in a vegetable patch. — *Above: Field beans growing in my vegetable patch. I planned to use these as green manure, but they looked so good I ended up eating them instead.*

Traditionally green manure is dug into the soil, but an alternative is to cut it and compost it. In the summer, unless you have a large garden, you may wish to save the space, but some green manure can be grown over winter.

Typically, though, I find the amount of waste generated by green manure doesn’t make a significant different to the amount of compost you can make. However, green manure offers other benefits for soil – for example, clover can fix nitrogen in the soil.

From the home, kitchen and office

Mixed waste in the compost heap. — **Image by herb007**

Vegetable and fruit scraps

Vegetables are full of carbohydrates, while fruit is full of sugar. Both are easily broken down by the bacteria in your compost.

While lemon and orange peels are more acidic than many other compost materials, your compost heap is perfectly capable of handling a few peels. Banana peels make a great compost material, as they are high in potassium, which is one of the nutrients compost bacteria need.

Vegetable and fruit scraps can be high in moisture, so do ensure you balance these out with dry, brown materials.

Coffee

Both coffee grounds and coffee beans are high in nitrogen and decompose rapidly. I used to collect these from my office in pre-covid times and put them in my HotBin, and you can also collect them from your local cafe.

Disposable coffee filters will also break down, and the extra carbon will help balance the ‘green’ coffee.

Tea leaves

Tea leaves are a fantastic compost material. High in nitrogen, they can safely be added straight to the ground as well as to the compost heap.

Do be aware that some teabags may contain small amounts of plastic, so you may wish to empty the tea bags from them. See our guide to composting tea bags for more information.

Newspaper and cardboard

Shredded newspaper is a great source of carbon and is relatively easily digested – worms seem to love it. It is advisable to shred it, though, and a whole newspaper may resist digestion.

Ripped and scrunched up cardboard also works well, and creates air space in the compost heap which helps speed up the compost heap without having to turn it to aerate it.

Again, thick cardboard takes longer to compost, and you may find that cardboard on the edges of the heap takes a long time to compost. You can use this to your advantage by using the cardboard as a wrap around the exterior of the heap to provide insulation and warmth.

You will find some sites advising you not to compost newspapers or cardboard because of ink. In the UK at least, regulations on ink are now so strict that polluting elements have been stripped out of the ink, and it shouldn’t be a threat to your compost or your plants. However, glossy/shiny cardboard is an absolute pain to compost, and is best avoided.

Shredded paper

When I am short of other brown material, I collect bags of shredded paper from the office to use in my compost heap.

In addition to adding carbon to the compost pile, it is also great way to absorb excess moisture. However, it can take quite a while to rot down. An alternative is to use it as bedding in a worm bin.

Wood ash

Wood ash, whether from your fire place or from your garden fires, can be a great amendment to your compost heap, as it is high in minerals, calcium and potash, and may improve the quality of your compost.

Be careful how much you add – studies have found that adding 20% or more can lead to the compost getting too hot and making the compost too alkaline.

I personally rarely add wood ash, as I tend to place my ash in a circle around tender young plants to protect them from slugs.

Learn more: Ash in Compost: 6 Powerful Benefits (and How to Use It Right!)

From the countryside and the beach

Seaweed is a fantastic addition for the soil – and it doesn’t even need to be composted.

Although it doesn’t contain much nitrogen, it is high in minerals and even contains hormones that encourage plant growth. See our section on seaweed in What to Compost in Winter for more information.

Ponds and streams can be a good source of high-nitrogen weeds as well, but be careful only to remove detached or excess growth.

Meanwhile, a walk in the forest (or many city streets) can yield large quantities of leaves in the autumn and winter. I even know one intrepid composter who keeps a sack and shovel in the boot for collecting leaves and animal dung in the countryside.

Manure (from herbivores)

Manure on a blue tarpaulin before being added to compost.

Manure is a superb compost material. In fact, the Rodale Book of Compost advises it should be the first item on your list. I often find that the addition of a small amount of chicken manure rapidly causes my compost to heat up. All manure from plant-eating animals is good for compost.

However, one word of warning. Many animals are now fed on hay which contains herbicides. Read my tale of woe with manure before taking any risk.

Learn more about using manure.

Unusual materials

Egg/oyster/claim/crab shells

Shells are an excellent provider of calcium. However, they can take an extremely long time to break down. Many composters choose to dry them and crush them into a fine powder before use, which makes the calcium more immediately available to plants.

Hair, both from humans and pets

This compost material is very high in nitrogen. In fact, 6-7 pounds of hair can contain as much nitrogen as 100-200 pounds of manure. It is easily available from your hairdresser, although mine did give me a very strange look when I requested a bag.

Also see: Can You Compost Hair – What The Science Says

Urine

Urine is very high in nitrogen. It can help to activate compost and balance compost which is high in brown compost material.

Out of date wine and beer

Some composters believe the yeast in these helps the compost process, especially if combined with the ammonia in urine.

Old potting soil

A bit of soil can help balance out very green piles, and can add useful microorganisms to the compost mix. I try not to add too much, though, as it’s not going to add new nutrients to the finished compost.

Blood meal

Experiments at the Rodale Research Centre added blood meal to compost at rates of 3 pounds blood meal to every 31 pounds of compost material. It resulted in a significant increase in compost activity.

Materials to be careful with

Most organic things can be composted with a combination of the right conditions and enough time. But those conditions can be hard to replicate in the garden.

Large items need to be ground up, while other items food needs to be buried in the compost heap and composted at a high temperature.

So while most of the organic materials below can be composted, they are for the serious composter who has the right tools, experience and conditions for the job.

Meat, dairy, cooked food: Can attract rats.
Fish: Great for soil, but very smelly, attracts pests. If you are feeling ambitious, I have been experimenting with a method for composting fish that seems (so far!) to eliminate odors.
Bones: Can be composted (even human bodies can be composted) but if not treated right take a seriously long time!
Grease, oil, fat: Can block up spaces for air in the compost heap. Can be pre-composted in a Bokashi bin.
Charcoal ash: Can contain a binding chemical harmful to your soil, and should be avoided unless you are confident chemicals have not been added.
Weed seeds: Should be avoided unless you can be sure of high temperatures in your compost.
Manure from carnivores: Dog and cat manure can carry pathogens, and should only be composted if you are sure you can achieve thermophilic temperatures.
Lime: Some composters add lime to their compost in order to adjust the PH. However, compost tends to end up with a stable PH even if acidic or alkaline at the start of the process. The Rodale Book of Compost also warns that adding lime can be harmful to the compost process if you are composting manure. (Update – a 2023 study did find benefits to adding lime to compost when the lime was combined with calcium magnesium phosphate).

Conclusion

If you’ve been struggling for ideas for materials to compost, I hope this sparks your imagination! Remember too, this isn’t even a comprehensive list, and you may well find other organic materials you can turn into black gold.

Just remember that if it’s fish, dairy or meat, stick to hot composting or trench composting. If you’d like to get your compost hot, don’t worry – it’s not that difficult! To learn how, read The Five Rules of Hot Composting next.

Compost Magazine

What You Can Compost: From Everyday Items To The Bizarre…