How often should I feed my worms?

Many beginner vermicomposters search message boards asking, “How often should I feed my worms?” The answer depends on the number of worms you have, the conditions of your bin, and the time of year.

red wigglers composting worms

Let’s assume that you recently purchased 500 worms from your local red worm composting seller for the sake of this example.

Measuring how much your worms eat

When you first add your worms to your bin, it will take a bit of time for them to get established. It is normal for your worms to explore their bin for the first week or two and not eat a lot of food. For this reason, you will want only to add 1/4th of a cup of blended food at each feeding. Wait until this food has disappeared until you feed again.

As your worms get established in the bin, you will notice that the blended food disappears faster and faster. This is because your worms are getting settled and a host of beneficial bacteria and microbes that help your worms process their food.

In the beginning, you will want to 1/4th of a cup and observe how much your worms are eating. Once you know how much food they consume over the period of 48 hours, you will get a good estimate of the size of your worm population.

DO NOT OVERFEED YOUR WORMS If you want to learn more about overfeeding, click here.

Worm Composting Containers tote bin with compost

What to feed your worms

Good foods to feed your worms include most fruits or vegetables (click here for the complete list of foods). The key to feeding them these items is moderation of any one time or variety.

For example, if you feed your worms predominantly fruit, you will likely notice an increase in fruit flies. If you feed your worms only potato and onion skins, your bin will reek of rotten produce. Moderation is key!

What should feed your worms

When feeding your worms, you want to make a nice mix of greens, squashes, apple cores, banana peels, root vegetables.

I make this work in my home by saving a few days of vegetable and fruit scraps in the refrigerator. When I make my ‘worm smoothie,’ I pick through the scraps, trying to get the greatest variety. If I have an abundance of one type of food, I will place the excess scraps in the freezer in the future.



This approach ensures your worms are getting a wide variety of foods whose nutrient value gets passed to the vermicompost you’ll later harvest. Diversity and variety also prevent the pH from quickly getting out of balance.

What shouldn’t give to your worms

You should avoid giving your worms garlic, citrus fruit, meat, cooked foods, oily foods (however, they love avocado), and feces. While in nature or a large outdoor compost pile, you can add many of these items without worry.

That is because your worms can avoid these items while other composters take over.

Meat tends to attract composters like black soldier flies. Too much citrus can raise the pH, or fruit can attract mites and fruit flies. Feces can increase the temperature of the bin, cause an odor, or attract unwanted pests. Other insects aid in decomposition, but they are not something you want to attract to your in-home worm bin.

Do your best to avoid the items listed above. If a few scraps make their way into the bin, it should be okay. However, consider those items, okay to add on accident, but not include the worm’s daily diet.

How to prepare your worm food

How much your worms can eat also depends on the method you use to feed your little vermicomposters. This is because they don’t have teeth but instead have a gizzard. If you throw in whole produce without chopping or blending, it will take your composting worms significantly longer to consume the food.

When you throw in a whole piece of produce, it will first need to decompose enough for the worms to eat. If this is the only way you can get started in vermicomposting – then it’s okay. It will result in slower growth of your worm bin and worm castings that you can use in your garden or houseplants. My motto is always to encourage people to get started and then figure out what works for them.

Blend food instead of throwing whole veggies to increase how fast the worms can eat the food.

If you want to increase how much food your worms can eat, there are several things you can do. Let’s discuss some ways you can prepare and store your worm food.

If you want to compost more food scraps and use your worm castings in your garden, you’ll need to do a little work.

That means chopping up the food scraps, adding grit, and freezing the food if you can.

Chopping up ingredients

The first step to increasing how many food scraps you can compost is chopping up the food. Even if you use your kitchen knife and make a few extra chops, it will help your worms. It will give them more surface area to munch on as the food decomposes in the bin.

water food scraps and egg shells in blender

However, if you want to take that another step further, you can use a blender. If you are headed to your local second-hand shop, a cheap blender can help you greatly increase the amount of food your worms can consume.

This is because you can essentially liquefy the food, and the worms do not need to wait for the food to decompose.

Add your food scraps to the blender. Add a little rainwater, if you have it, otherwise add filtered water and then blend. You can use a measuring spoon to add a tablespoon of food and see how long it takes them to make it disappear.

If you want to increase how fast the worms can eat the blended material, you will need to add grit for the worms to use.

Items you can use for grit

While we think of worms as soft, slimy items and grit being something that could hurt them, grit helps the worms eat and digest their food. This is because instead of teeth, worms have a gizzard, similar to chickens.

This means they intentionally swallow small pebbles and gritty items to save in their gizzard. Food passes through the gizzard, and those gritty items act as teeth and break up food bits even further.

A common household item you can use to add grit is eggshells. You can use a mortar and pestle, a plastic bag and a hammer, a blender to pulverize them as much as possible. You can add the pulverized shells to the food when you blend it or sprinkling it in the bedding every so often.

egg shells provide grit for worms

If you do not eat eggs or want a pre pulverized option, you can purchase pulverized oyster shells or diatomaceous earth in many online retail stores. You can use both of these items the same way you would use oyster shells.

Freezing your prepared worm food

In the beginning, you will likely have more scraps than you need on hand. After you’ve worked so hard to save various food scraps, you will want to save them for future feedings. Use an ice cube tray or use recyclable material to portion out the food.

Freezing expands the cells in the frozen food. When you thaw and feed the cube to your worms, it is even easier o digest than the food before freezing.

Summary

I hope you found this guide helpful in determining how often to feed your worms. There is no 100% certain answer on how much and how often to feed your worms. Start first by giving your worms a tablespoon of food and seeing how long it takes to disappear.

You can increase how much they consume with a little effort on your part. Ideally, you can put enough food for your worms to consume in a week. Any more than that, you are likely to upset the worm’s ecosystem and cause more problems than it’s worth.

Until next time, thanks for reading, and happy composting!