Vermicomposting is often talked about as the perfect solution for apartment or winter composting because it can be done indoors.
But some worm bins are more suited to indoor composting than others. For example, many people avoid homemade worm bins for indoor use because they’re more prone to leaks and bugs.
So, what’s the best indoor worm composter? The best indoor worm composter is the maze worm farm composter. It’s good looking, compact, and easy to harvest the compost from. There’s no risk of leaks and your castings will be well aerated which helps to prevent any smells.
The worm factory 360 has the largest capacity for the smallest footprint of any worm bin.
The maze worm farm is small enough to keep inside, and there’s no risk of it leaking.
The hot frog composter is completely self-contained and can double as a side stand.
The best indoor worm bins
These are my picks for the best indoor worm bins. They’re stylish and practical at the same time.
Maze Worm Farm Composter
Best all-round indoor worm composter
A fantastic option for smaller households is the maze worm farm. It measures 15 x 15 x 11 inches.
There are two trays that you can rotate as needed. This makes harvesting super simple because you only have to remove one tray to get to the castings. The trays also come with indents to stop them from falling down into each other and compacting the material within.
The maze worm farm has an open drain, meaning the leachate flows through the bin and is collected in a trap on the floor. This eliminates any risk of leaks because there’s never a build-up of fluid.
The open drain also ensures adequate airflow within the bin. There’s a catch tray to catch any worms or castings that fall through the drain holes so they don’t end up on your floor.
But, if you have pets or kids, you might find them more interested than you’d like in the tray of worm tea on the floor. It is nicely tucked away, so it depends on how curious your children/pets are.
If this becomes a problem, you can always move the bin out of reach, such as on a kitchen counter.
HOT FROG Living Composter
Most stylish indoor worm composter
The hot frog composter is another good-looking option that wouldn’t look out of place being used as a side table.
The maple wooden legs are stained and sealed so will last a long time and can support a good amount of weight.
It’s a tray-based system with built-in aeration points that enable 360 degrees of airflow. The trays have angled migration holes that make it super easy for the worms to move between them and a water retention channel that runs around the outside of the tray.
The water retention channel prevents the edges of the castings from drying out. The leachate makes its way down into the collection tray at the bottom. One downside is that there’s no spigot on this model so collecting the tea can be a bit awkward.
Biovessel – Eco living composter
Best kitchen worm composter
The biovessel is a bit of a different option, but perfect for indoors. It’s stylish and has space for you to grow potted plants using the vermicompost you’re creating.
If you like to grow indoor herbs you can keep this on your kitchen counter and grow your herbs in it!
The creators of the biovessel designed the bin’s shape based on data collected over 20 months of research. The final shape was determined to be the most suitable space for the worms, enabling the bin to be as effective as possible.
Included in the kit you get the vessel, cork lid, caps for the holes in the lid, a moisture/pH probe, a scoop, and a sprayer. The moisture/pH probe is a great addition to the kit and lets you closely monitor the conditions of the bin.
There’s no spigot to collect worm tea in the vessel, which means you need to keep a close eye on the moisture levels and make sure it’s not too wet.
4-Tray Worm Compost Kit
Best worm composter for small apartments
This worm composter is very small compared to the typical worm bin. It’s ideal for 1-person households or anyone who lives in an apartment with very little space. Othe worms bins can be quite bulky.
The whole thing measures just 9 x 12 x 8.5 inches and will easily fit under the sink or in another small cupboard. However, due to its size, the bin can’t process loads of waste, which is why it’s better suited for 1-person households.
There are 4 trays included, three for the worms and one to collect worm tea. One downside of the design is that the worm tea collection tap is quite low to the ground, and you can’t fit a bottle underneath to collect the liquid. However, you can easily solve this by raising the bin off the ground slightly.
Worm Factory 360
Best large capacity indoor worm composter
The worm factory 360 is a classic worm bin that works well indoors. It’s a large capacity worm bin but has a tray design, so the footprint is still pretty small at 18 x 18 inches.
The standard worm factory comes with 4 trays, and you can order up to 4 more. The trays only need to be added as and when you need them. The bin is ideal if you have a varying amount of waste throughout the year.
There’s a spigot for collecting worm tea, but you need to be careful that the spigot doesn’t get blocked. If a blockage occurs, then you might see some leaks. Regular cleaning will prevent this.
One cool feature is the lid. The lid is dome-shaped and doubles as a tray to hold the trays while you harvest the compost. This is super handy for indoor use where you won’t want to put the trays directly on the floor or kitchen counter.
Urban Worm Bag
Best worm bin for the garage
The urban worm bag offers a different style of vermicomposting: flow-through vermicomposting. You put the food in the top and then harvest the casting from the bottom. If the idea of playing around with trays sounds like too much effort, the urban worm bag is a great option.
The bag is made of a canvas material that’s breathable and makes it easier to control moisture levels. Due to this, there is no way to collect any leachate.
If you’re a beginner vermicomposter, it’s probably best to keep this bin in a garage or utility room rather than your kitchen in case you do end up with a leachate problem. You can put a tray underneath the bin to catch any leaks.
What’s important in an indoor worm bin?
When buying a bin for indoors, you want to buy one that’s not going to make a mess, smell, or attract bugs. Home bins are best avoided because they tend to have a few gaps and things where bugs can get in (or water out).
Type of worm bin
There are two main types of worm bins: tray bins and flow-through bins. Which one you go for depends on personal preference, both can work indoors, but they have different pros and cons.
Tray worm bin
A tray bin is also sometimes known as a stacking bin.
As one tray fills up with castings, you put another tray full of bedding and food on top. The worms migrate upwards into the new bin leaving behind finished compost. Once the worms have fully migrated, you can remove the bottom tray.
You can keep adding trays and the worms will keep moving upwards.
This method makes harvesting the castings virtually mess-free because they’re all contained in a tray. However, it can be quite a lot of effort because you have to lift all the top trays off to get to the bottom tray.
Flow through worm bin
A flow-through worm bin works on the same premise of worms moving upward through the bin to get to the food, but there are no trays involved.
The bin is all one container. As you put the food in the top, the worms go up to eat it, leaving their castings at the bottom ready to be harvested.
To harvest the castings, you have to open the bottom of the bin and dig the castings out. This can be a bit messy because the castings aren’t contained, but you don’t need to worry about removing any trays.
Leachate collection method
Most worm bins produce leachate, commonly known as worm tea. This is the liquid that seeps out of the compost. It’s important for an indoor bin that you have a way of dealing with this liquid to prevent it from leaking all over your floor.
There are three different ways to deal with the excess liquid.
The most common way is with a spigot – a tap at the bottom of the bin that you use to drain any excess liquid.
This is a good clean way of making sure the liquid stays contained in the bin until you’re ready to drain it.
This method’s downside is that if the spigot gets blocked, it can lead to a build-up of liquid that will eventually spill out of the worm bin. Checking the spigot regularly for blockages will alleviate this risk.
The next most common way is to use an open drain.
Bins using this method have holes in the bottom that the liquid can drain through and a tray to catch the drippings.
There’s less chance of leaks using an open drain because the liquid is free to drain as it needs, but you do have to make sure the tray is secure and won’t be disturbed by children or pets.
Also, sometimes casting and worms can fall out of the drainage hole. There’s usually a tray to catch them before they fall into the liquid collection tray, but this is something to be aware of.
Technically, if the worm bin is being run correctly, there should be very little leachate. Most bins are made with plastic, which isn’t breathable, so moisture has a hard time escaping. But if you use a more breathable material, you’re less likely to get a build-up of moisture and don’t need a leachate collection method.
However, if you’re not an experienced worm composter, it can be difficult to get the balance right. You may end up with a dripping wet bin.
If you’re composting indoors, chances are size is going to be an issue. You don’t want the bin to take up too much room, but you also need it to be big enough to handle your waste.
If you find you have too much waste for the bin, you can always freeze it until it’s ready to be used (or get a second bin).
My advice would be to decide where you want to keep the bin and then look for something that fits that space.
If you have an apartment, size can be even more of an issue. In this case, it’s useful to have a bin that can fit in a cupboard. Then you can be sure it’s out of the way.
If your bin is going to be on show, then aesthetics can be a concern. You want something that will look good in your kitchen or garage and not raise too many questions when you have visitors over.
It’s up to you what you think looks good, but hopefully there a few options above.
How to avoid fruit flies when vermicomposting indoors
Fruit flies are a common issue when it comes to worm bins and is definitely not something you want to deal with inside your home.
Here are a few tips to prevent a fruit fly infestation:
- Freeze all your waste before you put it in the bin. The cold temperatures will kill any eggs that have already been laid in your waste.
- Always put a layer of bedding over your waste when you put it in the bin. The deeper the food waste is buried, the less chance there is of fruit flies finding it.
- Set up a trap near the bin to catch any fruit flies that do find their way in. You can either use a venus fly trap or make your own.
To set up a fruit fly trap:
- Fill ⅓ of a jar with apple cider vinegar.
- Add in a squirt of dish soap. The dish soap breaks the liquid’s surface tension and means when the fruit flies land on the vinegar, they drown.
- Make a cone out of paper and put it in the jar, making sure it doesn’t touch the vinegar. Fruit flies find it very hard to fly upwards, so the cone shape effectively traps them and forces them into the jar. An alternative is to cover the jar with plastic wrap and poke some holes in it with a toothpick. Or use the original cover for the jar with a few holes poked into it.
- Leave the trap near your bin and check it every few days for fruit flies.
How to avoid smells when vermicomposting indoors
Vermicomposting works so well indoors because the worms eat all your waste before it has a chance to start smelling. However, sometimes things can go wrong.
Here are some tips to avoid odor problems when vermicomposting inside:
- Don’t overfeed the worms. If your worms aren’t finishing the waste before it starts to smell, you might be giving them too much food. Slow down your feeding rate and wait until the worms have finished most of their food before giving them some more.
- Make sure the worms aren’t too hot or too cold. Worms are most active between 57 and 77 degrees. They can become sluggish outside of these temperatures, which can result in the food going off before they eat it.
- Don’t feed them food they don’t like. Meats, oils, fats, and dairy are all difficult for the worms to digest. If you add a lot of these types of material to the bin, the worms won’t eat it. The food will sit there and start to rot. If there’s some food you notice the worms aren’t touching, remove it from the bin and don’t feed it to them again.
- Check the environment of the bin. If you notice worms crawling up the sides of the bin and on the lid, this is a sign they don’t like their environment. The bin could be too wet, too dry, or too acidic.