Worm Farm Reviews

What Do Worms Eat? A Vermiculture Food Guide

What do worms eat? The short answer is just about anything! Learn what kinds of food you can and can’t give to your composting worms in our guide below.

Reading time: 6 mins

what do worms eat?

Composting is a great eco-friendly and sustainable way to repurpose kitchen scraps and organic materials into nutrients that will help your plants thrive. Composting worms are typically used to help break down the vegetation in compost faster, which helps reduce odors and rot – and ultimately improves the composting process.

Composting worms flourish from a rich and balanced diet, so it’s important to know what to feed them to keep them and your compost healthy. Some foods should be avoided at all costs when it comes to helping your compost worms. If you’re wondering what foods to feed your worms and which ones to avoid, we’re here to help. Here is everything you need to know about what worms eat, and what foods to avoid. 

RELATED: Best Worms For Composting

Qualities of good food for composting worms

Certain qualities in food can help your worms grow and stay healthy. Composting worms favor food that comes from plants since plants have vitamins and nutrients that composting worms need. You’ll also want to make sure you’re feeding your worms food that’s easy to digest for them. Here are a few qualities you’ll want your food to have:

  • Moist
  • Soft
  • Cut into small pieces
  • Derived from plants

Foods to feed your composting worms

If you feed your worms a rich diet with the right foods, they will grow, thrive, and turn your compost into nutrient-rich soil that you can use to help your garden bloom. Here are foods you can feed your composting worms to promote a rich and healthy diet.

food to feed your composting worms

Coffee grounds and tea bags 

Composting worms love coffee grounds and tea bags as they’re a great source of nitrogen. You can add coffee grounds and tea bags to the bottom of your composting pile to help attract more worms.

Fruit and vegetables

Composting worms will eat a variety of fruit and vegetable scraps including banana peels, apple cores, carrot tops, and lettuce leaves. They can eat most fruit and vegetable scraps, and some of their favorites include lettuce, kale, honeydew, cantaloupe, squash, watermelon, and more.


Although they’re not soft, eggshells are a good source of calcium for composting worms. Break the eggshells into small pieces before putting them into the compost bin to make them easier to digest.

Read more about adding eggshells to your worm farm here.

Shredded paper 

Shredded paper and cardboard provide worms with a great source of carbon, which helps balance the nitrogen-rich food. Shredded newspaper with black ink is best, as color ink is not ideal. Avoid carbon and carbonless paper, as well as office paper since it’s bleached white. 

Grass clippings and leaves

Leaves and grass clippings are great for your composting worms as they’re a rich source of carbon, and can help balance your food scraps and dry waste. Don’t add too many green grass clippings as they tend to produce a lot of heat when they break down, which can kill your worms. It’s also best to avoid putting any fresh lawn clippings, native or evergreen leaves, and sticks or woody stems into your compost.

Qualities of bad food for composting worms

There are some foods that should be completely avoided when it comes to the health of your composting worms. Here are qualities of bad food to look out for and avoid feeding your composting worms:

  • Acidic
  • Toxic
  • Fertilizers
  • Have chemical compounds
  • Treated with pesticides and herbicides

Foods to avoid feeding to your composting worms

Composting worms aren’t picky eaters and while they may eat the food you put in your compost, that doesn’t mean it’s always good for them. Here are the top foods you should avoid putting into your compost.

foods your worms should not eat

Citrus fruits 

Citrus fruits are highly acidic and adding too much of them into your compost will upset the pH levels of your compost, and worms need a balanced pH to stay healthy. Avoid adding a large amount of citrus peels, pulp, or juice from lemons, oranges, and lime. This also goes for tomatoes, tomato sauce, and tomato juice. 

Meat and dairy products

You should never feed your composting worms meat, dairy products, or any other animal products. As they decompose, meat and dairy products like milk become rancid, attracting vermin and other unwanted visitors like raccoons.

Greasy and oily foods

Greasy and oily foods will also become rancid as they decompose and will create a powerful and unpleasant odor. Foods that are greasy or oily will cause the compost to become too wet and attract unwanted pests, so it’s best to avoid them completely. 

Onions and garlic

Avoid adding onions and garlic to your compost. Although they will eventually be broken down by the composting worms, onions and garlic are very odorous and create a strong odor when decomposing. This will attract unwanted pests and vermin – which you don’t want.

Pet waste

Don’t put any pet waste into your compost – whether it’s from a dog, cat, or any other pet, this can do more harm than good to composting worms. Pet waste can contain viruses, parasites, and toxins that are harmful to the health of your composting worms. It can also contain pathogens that are harmful to human health as well. 

If you have cattle manure or manure from other herbivorous farm animals, let the waste mature in the outdoor elements for a year. Fresh waste from these animals can contain too much urea, salt, and be too hot for the compost bin. 

Diseased plants and animals

You should never add any diseased plants or animals to your compost. Although it may seem harmless to toss a dying plant into your worm bin, if it’s diseased, the compost won’t have enough heat to kill harmful pathogens or seeds that can harm composting worms and come back the following season. 


Composting worms are useful for creating rich compost to feed your garden and are also great for the environment. Now that you know the right foods to feed your composting worms, you can help keep your compost healthy and thriving. Happy worm farming!

worm castings

RELATED: Worm Farming For Beginners

The site for independent worm farm reviews, worm farming guides for beginners and all things vermiculture.

Leave a Comment

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