27 Composting Myths That Will Save You Time and Money

Composting is an integral part of gardening that has been carried on for generations. That has led to a lot of composting myths. What can you add? What can’t you add? Is it difficult? Do you have to follow specific methods to make it work?

In this post I will answer all of those questions and more, by looking at 27 common composting myths.

Composting Is Complicated

There is no right or wrong way to compost. You don’t need 3 bins – heck you don’t even need a bin. You can compost hot or cold, or do what most gardeners do and carry out warm composting, somewhere between the extremes.

You can use a bin, or a tumbler or do what I do and use the cut and drop method where you don’t need any kind of container.

There are things you can do to speed up the process, like chop material into small pieces, turn regularly, adding extra nitrogen and start with a proper C:N ratio, however you can do none of these things and you will still get compost. It will just take a little longer.

Think about nature. The leaves drop in fall, and by late summer they are all composted. Nobody is turning them, or adding greens. It all happens and there is little you can do to stop it. Composting is as simple as you want to make it. Don’t believe all those composting myths you read about.

You Need the Right Ratio of Browns and Greens

This is really two composting myths in one. First of all, you don’t need the right ratio of material. Pile up any kind of organic matter and it decomposes. There are no greens added to the fall leaves in the forest.

Having a good ratio will speed up the process because microbes grow best with a ratio of carbon to nitrogen of about 30:1.

The second myth is that it’s not about a green and brown ratio, but a carbon to nitrogen ratio. You can learn more about this in:  How to Compost: Browns and Greens.

Compost Bins Need to Be in Sun

Composting happens faster when the pile heats up. Sun will help with this especially in colder climates, but it does not require sun.

In hot climates, a compost pile in full sun might dry out too fast, which slows down the process.

Composting Should be Done on Soil

This is a common myth that makes no sense at all. I suspect people think the soil adds the needed microbes, but everything you put into a pile is covered in microbes – you do not need to add more. Others believe composting needs the worms from the soil – that is also wrong.

You do not need the compost pile touching soil.

Compost Tumblers Make Compost in Two Weeks

Manufacturers of compost tumblers claim that you can make compost in two weeks and that is just nonsense. Compost tumblers do work but not as well as a large compost pile.

As microbes decompose organic matter they produce heat. A large pile helps to hold in that heat, speeding up composting even more. The volume of that pile, which is usually 3 x 3 x 3 ft, is necessary to produce a hot composting process. Tumblers can’t match that.

More about tumblers here: Compost Tumblers – Do They Work

Compost is Acidic and Will Affect Soil pH

Finished compost is nearly neutral, but the final pH depends on the material that went into it.

It will not affect the pH of your soil, unless you garden on pure sand, and then the effect will be minimal. Don’t add lime to compost to neutralize pH.

Compost Stinks

The composting process has almost no smell.

Fresh kitchen scraps do smell a bit for a day or two, but if you dig them into the pile you won’t notice the smell.

Don’t add too much high nitrogen material or meat and you will have almost no smell.

Compost is Finished in a Few Months

This is another common myth. Composting takes as long as it takes. In colder climates it takes much longer than in warm ones. A small pile or one with a high carbon ratio will also compost much slower. A simple pile of fall leaves can take more than year.

Even when you think it is “finished”, it’s not. To our eyes it looks fully decomposed because we can no longer see large objects like a banana peels, but on a micro scale it still consists of pieces of undecomposed material, and that is a good thing.

So-called finished compost will continue to decompose for another 5 years. As it does, it slowly releases nutrients for your plants. Think of it as a slow-feed fertilizer.

Composting Attracts Flies and Rodents

This is rarely a problem. Sure, a rodent might come and get a slice of bread and if you add a lot of rotten peaches you will probably get some fruit flies.

As the pile decomposes all of these will either leave or be killed. A few flies and rodents are part of nature. A compost pile does not breed more of these pests.

Add Compost Accelerators and Compost Starters

These products normally contain a nitrogen source or a microbe source, or both. They are not needed.

Adding extra microbes to get the composting process started is completely unnecessary. Everything you add to the compost pile is covered in microbes. You can’t see them, but they are there. You don’t need to add more.

Adding nitrogen can be beneficial if your carbon to nitrogen ratio is high because nitrogen will speed up the process. But it is not needed, and nitrogen fertilizer is usually much cheaper than special so-called compost starters. Peeing on it a couple of times will do the trick too.

Don’t Compost Cooked Food

I can’t imagine how this composting myth started. Cooked food contains about the same material as uncooked food. Sure cooking causes some minor chemical changes, but most of the molecules are the same in both. It is all organic material and it all decomposes.

Some people believe animals like cooked food better than uncooked and so it should not be used, but I have never seen any scientific evidence to support this theory. If you find some, post it in the comments.

Don’t Compost Meat

You can compost meat. What you need to understand is that it composts slowly, attracts animals and can smell. For these reasons most people don’t add it to a compost pile.

Don’t Compost Cheese and Fat

These can also be composted, but they compost slowly and can attract animals. Unless you do hot composting it is probably best to leave these out if you are dealing with large amounts. But who throws away a big pile of cheese?

Alternatively, you can bury them in soil and let them compost there.

Don’t Compost Starchy Food

Starchy food like bread and noodles contain a lot of carbohydrates which are long chains of sugars. Sugars are the favorite food of microbes so there is absolutely no reason not to add them to the compost pile.

Some people are concerned that rodents like bread. So what. They might come and find it in the compost pile. They then eat it, digest it and deposit their poop in the garden. The bread is just composted faster that way.

Don’t Add Onions or Citrus Peels to a Compost Bin

Citrus peels decompose slower than some other things, but they do decompose. The amount a normal home produces is not a problem.

I can’t imagine why anyone would think there is a problem with onions. Onions do have a low pH around 5.5, but that won’t affect the pH of a compost pile. Onions do contain more sulfur than other organic material, but not enough to affect composting.

Add Paper and Cardboard to the Compost

Paper and cardboard are made from organic material, but the cellulose in these products is difficult for microbes to digest, resulting in very slow decomposition. They also have a very high carbon ratio exacerbating the problem.

In most cases paper products are mostly intact at the end of the composting process. Unless you have a lot of nigh nitrogen material, it is better to leave out the paper products. Besides, there is no nutritive value in paper.

Don’t Add Weeds to the Compost Pile

In most cases weeds are really no different than other green plant material and they will decompose quickly.

Adding weed seeds can be a bigger problem, but if you weed correctly, and get them before they flower, this is not an issue. A hot compost pile will kill most seeds.

Some weeds, like bindweed and Canada thistle, have very tough runners that sprout new plants easily. I would keep these out of the compost pile. The best thing to do with them is lay them on a walkway or the lawn and let them dry out for a week. Then you can compost them or just leave them where you dropped them. Nature will make them disappear.

Add Tea Bags to the Compost Pile

The tea inside tea bags will easily compost, but the bags are mostly made from a plastic or paper material. Even when labeled as biodegradable, they don’t decompose in a garden compost pile, even a hot one. Either don’t add them or pick them out at the end of the process.

Don’t Compost Poop

Human and pet poop is really no different from farm animal poop. It all composts and adds much needed nitrogen to most piles: The Full Scoop on Composting Poop

There is a concern about spreading human infectious diseases. The risk is extremely low if the compost is used on ornamental beds, and only slightly higher in vegetable gardens. To be on the safe side, it is probably best to leave it out of the compost pile.

Should you compost cat liter?

Should you compost dog poop?

Don’t Add Diseased Plant Material

Most compost is made using yard waste. By fall every piece of it is covered with disease organisms. If you only used disease-free material, you could never make compost. Don’t worry about diseased yard waste.

Don’t use material infected with a virus – but that is uncommon in gardens.

Don’t Use Pine Needles – They Don’t Decompose

What happens to pine needles in nature? Do they pile up higher and higher each year? Have you seen 50-foot piles of pine needles in the woods? Pine needles must decompose since the ground under pine trees only has a thin layer of needles. If they decompose in nature, they will decompose in a compost pile. Sometimes myths can be debunked with simple logic.

Pine needles contain chemicals that can be difficult to decompose but you can use compost with them half decomposed.

Some people are concerned that the acidity of pine needles will interfere with the composting process, but this is another myth – they are not acidic once they are on the ground and only slightly acidic when green.

Add Eggshells to the Compost Pile

There is nothing wrong with adding eggshells to the compost pile, but they don’t decompose. They really don’t add much value to the garden.

Don’t Add Grass Clippings

Grass clippings should be mulched and stay right on your lawn, but if you remove them, they can be added to the compost pile.

If you create a big pile of green grass clippings they will start to stink. Grass clippings are high in nitrogen and moisture, which results in anaerobic decomposition, and that stinks.

The solution is simple. Let them dry for a day or two before piling them up. Or mix them well with a high carbon source like leaves.

There is one possible reason not to use grass clippings. If they have been treated with certain herbicides the chemical may survive the composting process. It won’t affect mature plants, but it may harm seedlings. Such grass can be composted, just don’t use the compost around seedlings.

Earthworms Speed Up a Compost Pile

There is a process called vermicomposting which uses worms to decompose organic matter but that is something completely different.

Adding worms to a cold compost process might help a bit although they will probably just crawl out of the pile into the soil. Adding them to a warm compost pile will kill them.

Earthworms are not part of the composting process. Granted they usually show up near the end of the process because they use the compost as food and I think that is why people think they are important during composting.

Coca-cola for Compost

The internet is full of secret concoctions for speeding up the compost process. One suggestion is to add coca-cola, another is adding molasses. These just add some sugar and do very little.

You do not need to add a secret sauce.

Add Compostable Plastic to Your Pile

So-called compostable plastic is NOT compostable in a home garden compost pile. Except for a few specialty sites it is also not compostable in municipal composting facilities. The whole topic of compostable plastics is a big green-washing effort by companies. Almost all of it ends up in landfill.

Keep Pets Out of Compost

Neither you nor your pets should eat moldy food from compost bins or the garbage. Mold can certainly cause harm to dogs.