When people want our recommendation for a good indoor vermicomposting system - either for beginners or those with more experience - there’s one in particular that just keeps coming up, almost every single time.
No spoilers here…it is of course the Urban Worm Bag (UWB) - and the reason for our praise is that it has most, if not all, of the attributes of a great indoor system:
Large capacity
The UWB has a volume of about 30 gal (~114 L), which makes it considerably bigger than most home-scale worm bins on the market (believe it or not, it’s even bigger than the Hungry Bin, which is only 20 gal). This helps to reduce the chances of overfeeding, while also increasing your output of finished worm castings (over time).
Durable Construction with Aesthetic Appeal
This is a well-put-together system that - in our humble opinion - looks pretty decent too! The tan-coloured “900D Oxford” fabric design, and attractive black metal stand, helps to make the UWB the sort of worm bin many people would happily have on display, not hidden away.
Affordable Price
Surprisingly, UWB pricing is similar to the (much smaller) Worm Factory 360, and is considerably lower than both the Urbalive Worm Farm (standard model - the compact model is in a similar price range), and the Hungry Bin.
Effective Continuous-Flow Process
The large, single-compartment flow-through design provides the worms with a much more natural vertical migration environment, versus what you find in stacking systems. This translates into a simpler, more effective process. Once the initial “priming” period (time required until the first harvest) is complete, castings can be harvested more regularly from the bottom, without the hassle of switching out trays etc.
Moist Environment with Great Airflow
Fabric bag systems are known for their excellent airflow (a highly valuable attribute for a worm bin), but also for their tendency to dry out really quickly. The UWB offers a happy medium between the two. It’s able to retain moisture quite well, while still offering a lot more airflow than most plastic worm bins.
Sturdy, Easy-to-Assemble Stand
It’s worth circling back to the stand, since it’s not uncommon for bag systems to require that you go the DIY route! Not so with the UWB. It comes with all the parts you need to build a really solid stand, nicely packed in a surprisingly small box (and you don’t need to be an Ikea engineer to set everything up either)!
Great Company with Excellent Support
Steve Churchill, founder of the Urban Worm Company, is continually working to improve the UWB design (and has done so multiple times already), based on feedback he receives from customers. He also offers excellent support and education via the Urban Worm Company website, and other channels, including a Facebook group set up specifically for UWB owners!
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While there’s no doubt that the Urban Worm Bag is a well-rounded system - one that should be on the radar screen of most vermicomposters - like any system, it’s not without its own set of limitations. Here is a handful of important ones to consider:
It Takes Up a Fair Amount of Space
The UWB footprint is a reasonable ~5 sq feet (0.46 sq metres), but it’s definitely not what you would call a “compact” indoor system. You won’t be able to keep it under your sink, or even inconspicuously tucked away in the corner of a room (although, it does at least tend to fit pretty nicely in a corner).
It’s Not Designed for Neglect
Yes, it offers increased moisture-retention in comparison to some other bag systems, but the fact remains that even UWBs need to be tended to fairly regularly. If you want a system that’s more “set-and-forget”, we recommend some form of plastic tub system.
It’s Not Designed for Outdoor Use
If you want a system you can keep outdoors for at least part of the year, the Urban Worm Bag might not be your best choice (something like a Hungry Bin would be a much better option). While it can technically sit outside, exposure to the elements will greatly reduce the life of the system over time. (NOTE: There are a variety of reasons you should be careful when keeping almost any small to mid-sized worm bin outdoors, so this downside isn’t solely limited to the UWB)
It Gets Heavy and Awkward Once Full
With great size comes…more inconvenience, at least as far as moving your UWB goes. If you’re looking for a bin you can easily relocate once it’s been up and running for a few months (or more), this might not be it.
It’s Free Draining
The convenient opening for harvesting castings at the bottom also allows for easy drainage of leachate. We’ll be sharing a set up approach that should help to reduce this outflow, but some drainage will still be likely, especially during the first few months of operation, so you will need some form of catch vessel sitting down below.
Final Thoughts
Choosing a worm bin is a personal decision - one that should be influenced by your available space, desired system location, experience level, budget, aesthetic preferences, and overall goals (among others). A bin we think checks off a lot of boxes is the Urban Worm Bag, and this is why we very often recommend it for those wanting to vermicompost indoors on a small-to-medium scale.
The excellent airflow, large size, and simple-but-effective continuous-flow design can provide the average home vermicomposter with a surprisingly effective castings-production system - much more on par with the CFTs many professionals use than what you can expect from a stacking tray bin or tub system.
Like any system, the UWB has its set of limitations and shortcomings, though, so be sure to weigh your options carefully, and have fun with whatever system you decide to move forward with! 😎
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To learn about how we recommend setting up an Urban Worm Bag, be sure to check out Part II in our UWB series: Setting Up Your Urban Worm Bag for Worm Composting Success! If you are looking for information relating to the ongoing care and harvesting of your UWB, check out Part III: How to Maintain and Harvest Your Urban Worm Bag.
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