What Do Worms Eat, Everything You Need To Know

If you’ve ever wondered "what do worms eat?", we love where your head is at and have wondered that too! While traditionally thought of as something entirely icky, worms can actually be quite valuable to our gardens and soils and can play a big role in helping us deal with all of the waste we are sending to landfills and/or incinerating.

Once I learned about all the things worms can do, I definitely developed a whole new appreciation for them. In this instance, we’ll be looking at vermicomposting. From what it is and what type of worms are used, to what worms eat and how to feed them. 

Quick links for:
What is vermicomposting?
What types of worms are used in Vermicomposting?
What to feed your worms
What not to feed your worms 
How to feed your worms 

What is vermicomposting 

Vermicomposting is basically using worms to create compost but it offers a much richer byproduct than traditional composting. With the help of microorganisms, worms break down and detoxify organic waste — turning it into a cost-effective soil amendment that helps plants grow better. 

Turning organic matter into their own waste called ‘castings’ is what makes worms so valuable to composting. In fact, they make one of the best alternatives to homemade plant fertilizer. The end product is a rich blend of vital plant nutrients including phosphorus, nitrogen, and potassium. It also contains microbes that actually help plants to grow. If you are particularly interested in the benefits of composting for plants you may also want to look into how to make compost tea. 

Best of all, vermicomposting is considered one of the most sustainable methods of managing organic waste. Especially where landfills and/or incineration are still the main processes used to manage our waste–which is not so great for the environment. 

Instead, organic waste which accounts for about 20% percent of everything we send to landfills can be diverted from the waste stream and turned into something useful. 

So, instead of contributing to more greenhouse gas (GHG) emissions, leaching, and other forms of pollution, both traditional composting and worm composting can be used to process organic waste and reduce the environmental impact associated with our existing waste management systems.

Redirecting organic waste from landfills also means reducing the amount of space we need for landfills which is actually a concern in some places. In fact, the US is expected to run out of landfill space in 18 years (according to an estimate back in 2018), with the Northeast of the country running out of space the fastest. 

Vermicomposting. Earthworms compost organic waste. Pin

In Canada, the City of Ottawa is actively figuring out how to encourage more residents to recycle and compost in order to avoid having to build another landfill because this can also be quite costly. In 2007, the City of Toronto purchased a new landfill and it cost about $200 million. Back in Ottawa, the Trail Road landfill is expected to run out of space between 2036 and 2038 (14-16 years from now). 

Composting and vermicomposting can help address these issues while adding value on several fronts. Vermicomposting doesn’t have a smell either so don’t shy away if you need to compost in an apartment. You can use some indoor compost bins

For those in cold climates don’t let the winter months deter you from starting your own compost.  The benefits of composting in the winter are totally worth it. 

What types of worms are used in Vermicomposting

As with everything sustainability, you really don’t want to force anything. Instead, you want to go with the flow and take advantage of how systems work naturally—nurturing them for the desired outcome. Where worms are concerned the principle is the same. The two main types of worms used are the red wigglers (Eisenia fetida) and the redworms (Lumbricus rebellus). That’s because they are easy to keep and actually prefer being in a compost environment as opposed to plain soil. 

If you want to get your hands on some worms, it’s recommended you buy them. You may be lucky enough to find redworms out in nature. Look for them in places like under rotting logs. You might even find them right in a compost heap. The problem is distinguishing them from other worms will be difficult. So buying them locally or online is really the thing to do here. One pound of worms should be good to get you started (that’s 453.5 g or about 1,000 individual worms). 

What to feed your worms 

If you’ve read our 15 Awesome Composting Facts you will know that worms can eat quite a lot. They need about half a pound (226.5g) to a pound (453.6 g) of food per pound of worms per day. For food, they prefer a higher carbon diet (or brown matter) but they can be fed many kinds of organic matter. However just as we have to know what not to compost, worms have their dislikes too—but more on that later. Here’s what they do prefer to munch on:

Brown matter your worms can eat: 

  • Dried leaves 
  • Shredded brown paper, newspaper
  • Shredded egg cartons and cardboard
  • Compostable coffee filters 
  • Ground-up eggshells
A bin full of worms and dirt. Pin

Green matter your worms can eat: 

  • Vegetable and fruit scraps like lettuce, kale, broccoli, pumpkin, melon rinds, banana peels to name a few
  • Food scraps like pasta (oil and sauce free)
  • Coffee grounds
  • Tea leaves 
  • Bread 
  • Grains 
  • Uneaten pet food 

Remember to rinse off any hot spices, sauces, oils, dressings, and cheeses because this can harm your vermicompost. Consider pairing a vermicomposter with a traditional compost for things that cannot go in your vermicomposting bin. 

What not to feed your worms 

Though worms are little soil superheroes and eat a lot of the same things as what is compostable at home, there are some no-no’s here too. In some cases, it is to avoid pests overtaking your bin, and in others, it is because the worms will not be able to process that kind of matter. 

  1. Fruit and veg scraps like citrus, onion, and garlic are to be avoided. Citrus or any other very acidic fruits can end up killing the worms if too much is added. Onion and garlic will eventually be broken down but will give off a strong odor.  
  2. Bones, and twigs.
  3. Salty foods.
  4. Greasy food. 
  5. Meat and dairy products. Avoiding this helps to prevent any unwanted smells or pests like maggots and flies. 
  6. Hot manure or pet waste. Hot manure or uncomposted animal waste can lead to temperature increases that are not suitable for the worms. Pet waste is generally not recommended in home composting systems where it will later be applied to food because of the pathogens it might contain.  
  7. Compostable Trash Bags. If they are actually compostable, they will take a lot longer to degrade than say your shredded cardboard. They are also not recommended in your home composter so I definitely wouldn’t add them here either.
  8. Plastic, Rubber, Cellophane. Whether they are biodegradable vs. compostable, or neither, you definitely don't want any of these items in your worm bin. Biodegradable products will take longer to degrade and you basically don’t want anything slowing down decomposition if your goal is to get usable compost. This waste will not bring anything positive to compost either. And they may even leave behind compounds that you don’t want in your plants or in your soil.

If you are experiencing rotten smells or the presence of unwanted lifeforms in your bin consider troubleshooting for common issues. They are usually caused by some form of imbalance which can be surprisingly easy to remediate. 

Infographic of vermicomposting. What to compost. Worm composting. Recycling organic waste, compost. Sustainable living, zero waste concept. Hand drawn vector illustration.Pin

How to feed your worms 

If we’ve got you considering starting your own DIY vermicomposting bin, here’s what you need to know about how to feed your worms. When it comes to composting of any kind, feeding is an important part of maintaining the balanced mini-ecosystem you are creating. Too much water, sunlight, or nitrogen, and the decomposition process goes awry. The same applies if there is too little of something. 

When it comes to vermicomposting, one trick is to create alternating layers of brown (carbon-rich) matter and green (nitrogen-rich) matter. Start by spreading a thin layer of green matter across the bin and then lightly covering it with the brown matter. Keep layering in this fashion. The top-most layer should always be a thicker layer of brown matter which will help prevent flies and odors. 

Make sure to break down everything you add to your bin into smaller pieces or give them a whirl in the food processor if you can. This helps your worms out and speeds up the decomposition process. How often you feed your worms will depend on how big your compost bin is. 

You can also keep a journal on how fast your worms consume certain things and adjust timing, quantity, and variety accordingly. If your worm population is growing, you are doing well. 

Final thoughts on what do worms eat

Good questions tend to lead to good answers and ‘what do worms eat’ certainly fits the bill. Turns out feeding worms some of all the waste we are setting ablaze or just burying in gigantic holes can help reduce our environmental footprint and add unparalleled value to our crops and soils. 

Combined with other sustainable practices such as traditional composting and low or zero waste practices such as cooking zero waste meals or creating a zero waste kitchen, we can really start to make a dent in tackling our waste problem. Committing to more ethical consumption patterns such as the 5 R's of zero waste or implementing sustainable practices in your home should also be part of the solution. It may not be easy, but nothing worth doing comes easy. 

Whatever you can do, any little bit helps so don’t worry if you can’t start your own vermicomposting system or create the zero waste home of your dreams today! You can adopt some zero waste cleaning habits, reach for a zero waste mop, or even try kitchen scrap gardening. Figuring out what to do with old plastic Tupperware is awesome too! Small actions count. 

And for any sustainable living essentials like home goods or plastic-free products remember to have a look around our Brand Directory

If you found this post helpful, please help someone by sharing this article – sharing is caring 🙂!


Share your thoughts

Your email address will not be published. Required fields are marked *