Vermicomposting is becoming more and more popular, especially in urban areas because of how much it speeds up the composting process.
Gone are the days of waiting years for your compost. With a worm bin, you can have high-quality compost in a few months. And because worm bins are a type of continuous compost bin, you’ll have a constant year-round supply.
But pick the wrong bin, and you might find yourself giving up before you’ve even really started. We’ve rounded up the best worm composters on the market to make sure you have a bin full of healthy happy worms.
Worm composting, or vermicomposting, uses worms to speed up the composting process. Red worms feed off organic matter and then poop it out in the form of worm castings. You can use the worm castings as compost.
Worms work quickly and efficiently to break down the food scraps you give them. The worms will devour their food before it starts to rot and smell, so the system is odor free. Because of this, lots of people decide to keep their worm farms indoors.
These are our top six picks for the best worm composters you can buy today. Plus two extra bins that didn’t quite make the list but we thought were worth mentioning.
The Worm Factory is the original worm farm and pioneered the stackable design that’s become so popular today. This is mostly because of how easy it makes harvesting the compost. It’s the second version of Nature’s Footprints worm bin and has a few improvements over the previous model.
A small change that we found surprisingly useful is the redesigned lid. Before it was just flat, but now it’s dome-shaped and doubles as a holder for the worm trays when you’re harvesting the compost. The legs are also slightly taller to allow for better ventilation.
The product comes with four trays but is expandable up to a total of eight; meaning you can adjust the size of the bin to suit your needs. If you’re feeling lazy and don’t want to harvest the compost, you don’t have to! When you have eight trays on the go, Nature’s Footprint claims that the bin has the largest volume for the smallest footprint of any home composter. The total footprint is 18″ x 18″.
One thing I really like about this composter is the fact it’s made in the USA. This cuts down on its carbon footprint because the bin doesn’t have to travel as far. Also, you can be sure the people who made it have been treated fairly – a big plus for me.
One quirk is that there’s nothing to stop the trays sinking down into each other. This means they can end up compacting quite a lot, and they definitely don’t stay as evenly spaced as they look in the picture. This isn’t usually a problem for the worms who like to live at the surface anyway. It’s more of a cosmetic issue.
The thing that sets this worm composter apart from the other options is the story behind it. Steve Churchill invented the urban worm bag in 2017 after his wife got him into vermicomposting. Since then, his business has gone from strength to strength.
The design leverages the fact that worms are surface feeders, and tend to live in the top 6-8 inches of soil. This means the worms will move up the bin as it gets more and more full, leaving the castings at the bottom.
To harvest the castings, all you need to do it unzip the bottom of the bag. If you’ve had any experiences with the first version of this bin, you might have had problems with the zip. Steve listened to the complaints about this and has fixed the problem with this most recent model.
Urban Worm prides themselves on their customer service and offers a lifetime guarantee on the worm composter as well as personalized help if you ever need it. They run a Facebook group that you can join and questions about the bag or worm composting in general.
The bag is made from a breathable material, so keeps the compost well aerated, and you can use the bottom zip to control moisture levels. The bag is strong enough to support over 120 lbs of compost. But it isn’t rodent-proof so is best kept inside. Don’t worry, as long as you follow the guidelines the bin won’t smell.
Learn more in our review of the urban worm bag.
The Vermihut Plus offers excellent value for money and is one of the cheapest options on the market, especially when it’s on offer! It uses a tray system and works in pretty much the same way as the Worm Factory 360 we featured above.
The lid is lined with coco coir in a unique design that stops any smells from escaping and helps keep the bedding moist. The coco coir mat also prevents any fruit fly infestations, while at the bottom of the worm bin, there’s an ant trapper to stop ants from overtaking.
Another innovative feature the bin has is a ‘worm saving tray’ that catches any worms before they fall into the leachate collection tray. This way they can easily climb back into the bin rather than drowning in the liquid.
At full capacity, the compost bin can accommodate up to 10 lbs of worms which means it can reduce up to 5 lbs of waste a day. This makes it the perfect bin for large families with a lot of food waste. The instructions that come with the Vermihut are quite basic. If you’re a newcomer to vermicomposting, I’d advise you to disregard them and use a more detailed guide like our article on the basics of worm composting.
Biovessel is a modern-looking bin that was made for urban composters. There’s a plant pot holder in the lid that allows you to use the compost as soon as the worms produce it. Since the bin is small enough to fit on your kitchen counter it’s perfect for growing herbs in.
If you have kids, this wormery a great tool for teaching them about composting and getting them involved. If you start them young, they’re bound to grow up to be keen composters too!
The curved tray looks good but also serves a purpose. The shape is based on multiple data points and designed so that the worms can work to maximum efficiency, decomposing your waste as fast as possible.
The Biovessel has a smaller capacity than most bins, so it’s best for smaller families or to use as a supplementary indoors bin. One downside is that currently there’s no way to harvest the leachate (worm tea), so you have to keep a careful eye on moisture levels in the bin.
Hot Frog has taken the traditional stacking worm composter and made it stylish. The bin won’t look out of place in an apartment kitchen, and you could even use it as a side stand.
Inside the bin, there’s a water retention channel running around the outside of the trays which collects water and prevents the edges from drying out. You can drain any other excess liquid using the spigot at the bottom.
Some users have reported that the valve can become blocked with dead worms who’ve strayed into the collection tray. If you find this becomes a recurring issue you can fix it by fashioning a worm block out of some leftover plastic.
The composter is made using BPA free, UV inhibited recycled materials so won’t become brittle from sun exposure. The double-walled base and ceiling help to protect against temperature swings. That said, I wouldn’t be comfortable leaving the Hot Frog outside in the winter without extra protection.
Like the Urban worm bag, the Hungry Bin is a continuous flow through worm farm. As you add more food waste, the worms move towards the surface and the castings fall to the bottom. The top of the bin is purposefully wider giving the worms more surface area to feed on your scraps. This helps to speed up the composting process.
The bin is on wheels so it’s really easy to move around. This is useful if you live somewhere where the temperature varies quite a bit and you find yourself having to move the bin indoors.
Hungry Bin has done away with the taps that you see on other models to prevent any issues of blockages. Instead, the liquid just drains straight through into a tray that sits on the floor.
One thing we don’t like about this worm farm is the price. It’s the most expensive compost bin we’ve featured, although lots of reviewers say the high quality means it’s worth the money.
The worm composters above are, in my opinion, the best worms bins you can buy. That said, I also wanted to give the two options a shout out as they both offer something unique.
If you live in an apartment and are limited on space then be sure to check out this 4-tray composter from Quest. It’s small enough to fit under your kitchen sink so won’t take up any valuable floor space. It’s also useful for people who don’t generate enough kitchen waste to justify having one of the bigger worm bins.
You can bury this underground bin from Tumble Weed in your garden and skip the step of transferring the compost from your bin to outside. The bin turns your vegetable patch into one big worm farm. The worms can move freely in and out of the vessel depositing their worm castings in the surrounding soil.
Once you have the bin you need a few more things before you can get started:
You can’t use any old worms in your worm farm. They have to be red wrigglers which are different from the standard earthworms you find in your garden. If you can’t find any red wigglers locally, we recommend using Uncle Jim’s red worms. I’ve used these worms for years and never had any problems.
For bedding, you can use a wide range of materials with shredded paper being one of the best choices. I also like to use coco coir because it comes in compressed blocks, which means it’s easy to store. It’s useful to have as backup bedding for when you run out of organic waste materials to use. You can also use it in your composting toilet as a cover material.
In terms of food, the worms will pretty much eat all your fruit and vegetable waste, as well as any leftover rice pasta, or bread you have. Just like with regular composting, it’s best to avoid meats and dairy because this can cause smells and attract pests (unless you use bokashi).
Another useful tool is a thermometer. You don’t need one, but it helps you monitor the conditions within the bin and keep the temperature optimum for your worms.
You’ll see a lot of people say that red wigglers can eat around ½ their weight in food each day. This is technically true, but only likely if conditions are optimal. For most home worm bins this will be an overestimate, especially if you’re a beginner. Remember the worms also eat their bedding which counts towards their food for the day.
I tend to feed my worms about 20-30% of their body weight a day and find this works well.
In most home worm bins the worms will eat 30% of their body weight in food per day
As a rough guide, 1000 worms weigh 1 lb, so will eat 0.3 lbs of waste each day. Say your family produces 3 lbs of waste every day you’ll need 10,000 worms for your bin. This sounds like a lot! But remember your worms will reproduce quickly, so you don’t need to buy that many worms. 1-2 lbs of worms is usually enough to start with.
At its simplest, a worm bin is a container with holes for ventilation and a lid to stop the worms escaping. Most bins are made of plastic and raised off the ground, so they don’t attract unwanted pests.
Here are four things we recommend thinking about before you purchase a worm farm:
Worms bins shouldn’t require much maintenance, but about once every 4-6 months you’ll need to harvest the worm castings. Certain bin designs make this more straightforward than others. There are two main types of bins, stackable and flow-through.
With stacking bins you wait until the bottom tray is complete and free of worms, then you can simply remove that tray. In flow-through bins, the worm castings fall naturally to the bottom of the container while the worms stay at the surface. Generally, you can open the bottom to harvest the compost.
Perhaps the most important thing to decide is how big you need your worm composter to be. If you’re keeping it inside and are limited on space, then make sure to check the dimensions of the product and see if it fits where you want it to go.
Another consideration is how many worms you need, and then how much space this amount of worms need. As red worms are surface dwellers, it’s the surface area of your bin you need to pay attention to.
Composting worms prefer to live in the top 6 inches of bedding
For the average worm composter, you should aim for 1 square foot of space per 1 lb of worms. Beginners will want to allow slightly fewer worms per square foot.
If you’re at all familiar with composting, then you’ll know it’s essential to keep your bin well ventilated. Your worms need oxygen to survive, and proper airflow also helps stop you worm farm from smelling.
Most worms bins have taken measures to enable adequate airflow. But they tend to be quite conservative on any aeration holes because the more holes in the bin, the more likely it is that worms will escape.
I like to drill a few extra holes into my worm bins to increase ventilation, but I keep mine in a shed so don’t need to worry as much about worms escaping as much.
Fruit and vegetable waste is naturally soggy and can create moisture in the bin. A good worm bin should have a way for this liquid to drain out. If you don’t drain excess fluid, you risk drowning the worms.
Leachate, or worm tea, being drained from a worm bin
Lots of people refer to this liquid as worm tea, but this is incorrect. The liquid is actually leachate. You can use it as liquid fertilizer, but it’s not as nutritionally valuable as real worm tea.
If you want to learn how to make real worm tea take a look at our ultimate compost tea recipe.
The best worm composters offer excellent value for money, an environment your worms don’t want to escape from, and make it easy for you to collect the compost.
If you’ve bought one of the bins I recommended, I’d love to hear what you think about it.
Veronica has a passion for all things eco-friendly. After growing up on a farm in Ireland, she went on to study Chemistry and Environmental Sciences. Veronica has also volunteered in many sustainability roles, including conservation efforts in Bangladesh and teaching Environmental Sciences to schoolchildren in Kenya.