A Super Simple DIY Vermicomposting Bin

Vermicomposting, or composting with worms, is an easy way to recycle kitchen scraps and create high-quality compost for your garden or container plants. The DIY vermicomposting bin I’ll show you how to build below doesn’t take up much space or require much effort. When maintained properly, it has little to no smell and can easily be kept in the kitchen.

Although premade worm composting systems for the home are available, it isn’t necessary to spend a bunch of money on a fancy system. I built my DIY vermicomposting bin with two five-gallon buckets and a drill. It’s super easy to make and will provide compost within a few months.

If you’re interested in other composting methods, check out my articles below:

In this guide, I’ll lay out the steps I used to build my worm bin out of two 5-gallon buckets, and teach you how to maintain it and harvest your vermicompost.

I’ll also cover some common problems you might encounter with your vermicomposting system and how to solve them. Let’s get to it!

DIY Vermicomposting Bin Materials

To get started with your vermicomposting bin, you’ll need the following materials:

Two 5-gallon buckets. You can use regular plastic buckets or opt for food-grade plastic.
One 5-gallon bucket lid. This can be a lid made for 5-gallon buckets, but it doesn’t have to be. Even a piece of plywood will do.
Bedding material, such as shredded paper, dry leaves, or coco coir.
Organic waste, including fruit and vegetable scraps.
Red wiggler worms, Eisenia fetida. Wait to order worms until the day you build their bin.

Tools

The only tool you need is a drill with a medium-sized drill bit (a 3/16” or ¼” drill bit will do).

Building Your DIY Vermicomposting Bin

Here are the steps to build your DIY vermicomposting bin:

Drill holes in one of the buckets and the lid
Assemble the Bin
Add Bedding Material
Add Organic Waste
Add red wiggler worms

1. Drill the Bucket(s)

Using a medium-sized drill bit (3/16” or ¼” work well), create ventilation holes in the sides and bottom of one of the 5-gallon buckets (or two of the buckets if you have three buckets and want to build a two-tiered bin).

Space the holes evenly around the upper part of the rim, where they won’t be covered by the lower bucket, about 2 inches (ca. 5 cm) apart. I used a 3/16” bit and drilled two rows of 16 holes for a total of about 32 holes around the rim of the bucket.

Drill twenty to thirty holes in the bottom of the same bucket to allow excess water to drain. The bottom holes will also allow the worms to migrate between buckets in a two-tiered system.

If you’re building a two-tiered system, drill a second bucket the same as the first.

Drill more holes in the lid for ventilation, again shoot for about 20-30 holes in the lid.

2. Assemble the Bin

Stack one drilled bucket with the bucket that isn’t drilled on the bottom to catch drips.

If you’re using three buckets for a tiered vermicomposting system, hold off on adding the third bucket until after the first tier is established and ready to harvest, which I’ll cover in the next section.

3. Add Bedding Material

Place a layer of bedding material in the bottom of the assembled bin. This bedding can be any carbon-rich organic material, such as shredded paper, shredded cardboard, straw, or coco coir. Even dry leaves will work, although there is a risk of introducing pests to the system when using materials from outside.

My favorite bedding material for starting worm bins is coco coir. For bedding added with each feeding, I prefer shredded paper.

Start with six to ten inches of bedding. Add enough water to fully moisten the material without any excess moisture. If you take a handful of the bedding and squeeze, very little to no water should come out.

4. Add Organic Waste

Add a handful or two of fruit and vegetable scraps, burying a couple pockets of it in the bedding. The scraps should be cut into small pieces, and (optionally) frozen for 48 hours prior.

See below for lists of what to feed and what not to feed red wiggler worms.

Cutting up the scraps helps them to break down quickly, reducing the chance of unpleasant smells developing, and making food available to the worms more quickly. Freezing destroys any fruit fly eggs or larva that might be hiding in the scraps.

Ideally, give the scraps a few days to start breaking down before adding the worms to their new home. However, if you have worms in waiting, they can be added at the same times as the bedding and first bit of scraps.

5. Add Red Wiggler Worms

It’s best to wait a few days after setting up the bin before adding worms. This allows the initial organic waste to begin decomposing and creates a worm friendly environment. Remember, worms eat rotted and decomposed scraps, not fresh ones.

Red Wiggler worms (Eisenia fetida) are the best species for vermicomposting.

I’ve purchased red wigglers from Uncle Jim’s Worm Farm twice, and have been very happy with them. I’m also affiliated with the company, so if you choose to purchase from Uncle Jim’s, please consider going through my link to help support this website.

Get your red wiggler worms here!

If you’re purchasing your worms online, order them the same day you build your bin. By the time your little friends arrive, their home will be ready for them.

Wherever you get them, make sure to confirm that you’re ordering Eisenia fetida. Different species are sometimes sold as “red wigglers.”

As soon as your red wigglers arrive, remove them from their packaging and place them, along with any bedding they were shipped in, into their new home. Follow any instructions provided with your worms. They may need to be rehydrated before placing them in the bin.

Using and Maintaining Your DIY Vermicomposting Bin

Now that your vermicomposting bin is set up, it’s time to start using and maintaining it. Here’s how to keep your worms happy and your compost thriving:

6. Feed the Worms

Prepare food scraps by cutting them into small pieces and freezing them for 48 hours prior. These steps are optional, but can prevent some common problems that occur with vermicomposting bins.

Feed your worms 1–2 times per week. Make a little hole in one part of the bedding and add a small handful of vegetable and fruit scraps. Gradually increase the amount as the worm population grows, and rotate the location each feeding.

Be mindful to not overfeed your worms. Overfeeding can lead to odors, pests, or other issues. Check the bin for remnants of the previous feeding to keep tabs on how much your worms are eating. You may be surprised at how much food they can go through after a few weeks!

What to feed composting worms

Most fruit and vegetable trimmings are perfect worm food, and will make up the majority of your worm’s diet (in addition to the bedding material). Other kitchen waste can also go to the worms. Here is a short list of some foods safe for the vermicompost bin. (list modified from Uncle Jim’s Worm Farm article, What Can I feed My Worms?)

banana peels
melon rinds
apple and pear cores and skin
lettuce, spinach, and other leafy greens
broccoli stalks and other brassicas
potato and sweet potato trimmings
carrot tops and peels
pumpkin and summer and winter squash
eggshells
coffee grounds
bread
grains
plain pasta
tea bags and coffee filters

Scraps to avoid feeding worms

Some foods shouldn’t go into the vermicompost bin, either because they aren’t good for the worms, cause problems with the ecosystem of the bin, or take too long to break down. Here’s a short list of things to avoid putting in the worm bin.

meat
dairy products
oily foods
onions
garlic
citrus
pet food
avocado pits
corn cobs

7. Regularly Add Bedding

With each feeding, add bedding material to the bin.

Aim to add about double the amount of bedding material as food scraps. This balances the nitrogen-rich food scraps with carbon-rich bedding material, as is important in any compost system.

If you started your bin with a lot of bedding, you may not need to add more initially, but it’s good to get in the habit of adding fresh bedding each feeding.

To make it easy, keep a container of fresh bedding next to your bin.

8. Monitor the Moisture Level of Your Bin

Each time you feed your worms, take note of the moisture level. It should be similar to a wrung-out sponge.

If the bedding material feels too dry, add a small amount of water. However, never pour water into the bin. Instead, mist it with a spray bottle.

If it’s too wet, add more dry bedding material to absorb the excess moisture.

Typically, food scraps will have plenty of moisture to keep the bin hydrated. Usually it’s simple to regulate moisture in the bin by adjusting the moisture of the bedding you add with each feeding.

If liquid drips into the bottom bucket, this is a sign that the bin is too wet. This liquid is called leachate. Although this is a normal part of vermicomposting, it’s best to minimize leachate, and it’s perfectly fine (better even) if no leachate comes out of your worm bin.

Speaking of leachate…

Don’t confuse leachate with compost tea!

The two are often confused but leachate and compost tea are two very different things.

Leachate, as mentioned above, is the liquid that “leaches” out of vermicompost bin during the composting process. Leachate can be very strong and it isn’t a great fertilizer.

I dump mine into my outdoor open-air compost bin, but some people dilute it with water and use it as a fertilizer. Proceed with caution if you choose to do this, as it can harm plants if it’s highly concentrated or applied directly to foliage.

Compost tea is an excellent fertilizer and can be made by soaking worm castings (finished and harvested vermicompost) in water and aerating it for a few days with a bubbler. I’ve yet to make my own worm tea, but maybe some day I’ll try it and write a post on it!

Harvesting Vermicompost from Your DIY Bin

After a few months, the worms will have processed the bedding material and food scraps into worm castings, or nutrient-rich vermicompost. Here are two options for harvesting your vermicompost.

Option 1- Dump and Sort

If you only have one tier in your vermicompost bin, the simplest way to separate the compost from the worms is to dump the entire contents onto a tarp outside. Follow these steps:

Lay out a tarp or large piece of cardboard on the ground outside
Dump the contents of the worm bin onto the tarp or cardboard. After a few minutes the worms will burrow down to escape the light.
Remove the top layer of compost.
Wait a few more minutes then remove another layer of compost. Repeat this until you’re left with mostly worms.
Return the worms to the bucket with fresh bedding and food.

Option 2 – Add a Second Tier

Adding a second tier to your bin will allow the worms to “self-sort” by migrating up, out of their castings to fresh bedding and food. Here’s how:

Get a third 5-gallon bucket that stacks with your original two buckets.
Drill holes in the new bucket the same as in the original bin.
Stack the newly drilled bucket on top of the original bin.
Place fresh bedding material and food in the top tier and replace the lid.

As the worms run out of food in the bottom layer, they’ll naturally migrate up through the holes in the top bucket, leaving their castings behind. You can then lift the top bucket out to access the worm castings below.

If you find some worms in the bottom layer when you harvest, don’t worry. Some may stay behind. Just pick out the few stragglers by hand and place them into the new bedding. Or simply leave the few stragglers in your finished vermicompost, setting them free in your garden.

Troubleshooting Common Vermicomposting Issues

Here are some common problems that might occur with your DIY vermicomposting bin. This information is based on my personal experience along with this article from Cornell University.

Worms Are Escaping or Dying

Finding dead worms in your bin, or escapees, can be alarming, and should be addressed as soon as you notice the problem to avoid losing your whole worm population.

If you are finding dead worms in your bin or worms are escaping or trying to escape from your bin, here or some possible reasons why this could be happening.

The bin is too wet
The bin is too dry
The bin is too hot or too cold
There isn’t enough air circulation

How to Fix Worm Death in Your Vermicompost Bin:

Check for the above conditions in your bin and address them with the following suggestions.

If the bin is too wet, pour out any water from the bottom bucket and add dry bedding material to absorb excess water.
If the bin is too dry, add moistened bedding material or spray the contents with a fine mist of water.
Keep the bin between 55 and 77 degrees F (12.8-25 degrees C), either indoors or in a shady location outdoors in a moderate climate.
If you suspect lack of air circulation is the problem, add more holes or larger holes to your bin and lid.

Odor Problems in the Worm Bin

If your worm bin smells bad, it might be from too much moisture, not enough air, over feeding, or not adding enough bedding material.

How to Fix Odor Problems in Your Worm Bin

Check the moisture levels in the bin. If it’s too wet, hold off on adding more water and add dry bedding material to absorb excess moisture.
Add ventilation holes if you think the bin isn’t getting enough air.
Check for excessive rotting food scraps. Remove any foul-smelling scraps and reduce the feeding schedule.

Fruit Flies in the Worm Bin

Flies are attracted to rotting food scraps, and can become a problem in vermicompost bins. I have solutions for both prevention and mitigation of fruit fly problems in your worm bin.

Fruit Fly Prevention

Prevention is the best solution for fruit flies. To avoid developing a problem with fruit flies do the following:

Freeze food scraps before adding them to the bin. This destroys any fruit fly eggs harbored in the scraps.
Cut food scraps into small pieces to accelerate decomposition and minimize the time available for infestation to develop.
Bury new food scraps in the bedding and don’t leave any scraps on the surface.
Keep the bin contents covered with a layer of damp cardboard, fabric, or even a few layers of newspaper to prevent fruit flies from accessing the contents.

Fruit Fly Mitigation

If you already have fruit flies buzzing around your vermicompost bin, there are ways to get rid of them.

Here are some ways to fix an existing fruit fly infestation:

Remove rotten food scraps from the bin to eliminate egg-laying sites for fruit flies, and implement the preventative measures above.
Temporarily air out the bin by leaving it uncovered outdoors to reduce the fruit fly population.
Set up flypaper strips or traps near the bin to capture adult fruit flies.
Set up a vinegar fly trap next to your bin (not in it). To make a trap, pour some apple cider vinegar in a small dish or bottle and add a couple drops of dish soap. The flies will be attracted to the vinegar and unable to escape.
If the above solutions aren’t enough to solve your fruit fly problem, remove as many worms as you can from your bin and start a fresh bin with them. Unfinished compost can either finish composting in an outdoor bin or you can freeze it to kill the fruit flies and add it back to the bin slowly over time. Any worms or worm cocoons will also be destroyed by freezing, so use this only as a last resort if you have no other options for dealing with the fruit fly infestation.

Conclusion

Congratulations on setting up your very own DIY vermicomposting bin system! By now, you’ve learned how to create a simple yet effective bin, feed your worms, harvest nutrient-rich vermicompost, and maintain your system. With just a little effort and attention, you’ll be producing black gold for your garden in no time.

I’ll leave you with a picture of a worm cocoon my daughter and I found while exploring our bin the other day.

And just for fun, here’s another picture of some red potatoes we found growing in our vermicompost bin that must have sprouted from a chunk of potato I’d thrown in.

Remember, vermicomposting is not only a smart way to reduce waste and enrich your garden soil but also a fascinating process to observe and participate in. So keep experimenting, learning, and enjoying the process.

Happy vermicomposting!