The Urban Worm Bag

Effective Flow-Through Vermicomposting Made Simple!

Once upon a time, I made a silly “worm bin” called the “Creepy Pants Vermicomposter“. From a “successful vermicomposting” standpoint, the experiment was a bit of a dud.

The jeans got moldy, and I don’t think my wife was too fond of (what looked like) half a body dangling from the rafters in our basement laundry room (especially with my mother-in-law coming for an extended stay).

So the project was somewhat short lived…

…But amazingly, it started the ball rolling towards bigger and (much better) things.


Robin Crispe – a regular follower of the RWC site – was somehow inspired by those moldy, “creepy” pants hanging down in my basement.

She got creative, and put her sewing talents to the test, designing a stylish, yet surprisingly-effective vermicomposting system.

She called it… the Worm Inn!

Robyn eventually decided to move on to other endeavors and the Worm Inn brand was taken over by Jerry “Worm Dude” Gach, who has continued to “carry the torch” to this very day. He has even added some improvements along the way, such as the single zipper (vs double zipper) closure – effectively reducing the chances of flying pests getting in or out – and a kit that helps people make their own PVC stand.

I myself have used (and loved) Worm Inns for years now, and I have written about them extensively on the Red Worm Composting blog. But, in spite of my keen enthusiasm, I’ve had some nagging issues relating to the design that I would have loved to have seen improved upon.

As you can probably guess, the story does not stop here!

2017 – And The Arrival of a New Player

In early spring of 2017, my good friend Steve Churchill decided that rather than waiting around for future Worm Inn improvements he would come up with his own “worm bag” flow-through system.

This is a guy who doesn’t mess around…

…and in mid-fall of the same year, the “Urban Worm Bag” (UWB) was launched!

Some of the “complaints” (from others and myself) about Worm Inns over the years have included:

  • Can dry out too easily
  • Doesn’t come with an easy-to-build, sturdy stand (even the “stand kit” requires you to purchase building supplies)
  • Screened lid (which I absolutely love) can be damaged or even destroyed very easily
  • Hand made so dimensions can be off (making it difficult to put on stand)
  • Toggle string at bottom can sometimes break down (I’ve had no issues with this)

The Urban Worm Bag is quite similar in appearance to the Worm Inn Mega (as you can see in the image) – but there are some really interesting differences!

Urban Worm Bag – The KEY Improvements

1) Easy-to-Assemble, Sturdy Metal Stand – This alone is a game changer! No trips to the hardware store, no spending even more money, no cutting, no hassles! It literally took me about 3 minutes to put mine together!

2) Much Bigger Hanging Loops – these should help to distribute the weight much better than the small loops of the Worm Inn (although I’ve always been impressed with how tough they are – and have never had one rip loose, even with VERY full Megas).

3) Solid Fabric Lid – As much as I always liked the screened lid of the Worm Inn, from a durability and shading standpoint, I think this is new feature is fantastic. And it also ties in with the next point…

4) Greatly-Improved Moisture Retention. The fabric used for the UWB has a more rubberized quality about it. Initially I thought this might be a “negative” (one of the best features of the Worm Inn is its breathability) but Steve compensated by making the Urban Worm Bag somewhat wider and somewhat shallower than the Mega, so it should have a more ideal surface-area-to-volume ratio. So far I have been blown away by the almost-perfect aeration/moisture balance my UWB has.

5) The Zippered Bottom Pocket – I really wasn’t sure what to think about this one at first – I have always like the drawstring with tightening toggles that Worm Inns have. But I absolutely love this feature now! It serves as a great starting zone for your “false bottom” and I am even using it to test moisture levels and provide more aeration.

6) The Price – It can be tough to get people excited about vermicomposting given how expensive it can be to get started!

UPDATE: Steve has now released a newer version of the UWB – to learn more about the design improvements be sure to check out this blog post: The Urban Worm Bag 2.0

Consider a system like the “Worm Factory 360” – quite possibly the most popular home system on the market. Just the base package is $119!!before shipping…before buying worms etc.

I have worked extensively with them myself, and while they are fine, I can quite honestly say that they don’t hold a candle to either the Worm Inn Mega or the Urban Worm Bag (both of these so MUCH bigger and much more effective) – and this is why I have never wanted to sell WF 360s myself.

Moving on to the Worm Inn Mega – fantastic option but it is not cheap…even without any sort of stand (and of course worms) you’re likely looking at between $120 and $130.

Steve’s “regular price” for the Urban Worm Bag – that includes a sturdy metal stand & U.S. shipping is only $109. I keep telling him he is pricing it too low, but he won’t listen to reason! lol

1 Urban Worm Bag (USA)
(with Metal Stand, Free Shipping & Support)


2 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


3 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


6 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


The Problem With Most Plastic, Enclosed Worm Bins…

…Is that they just don’t have the air flow required for an “optimized” vermicomposting process!

Don’t get me wrong. I’m not trying to convince you that you can’t vermicompost effectively with other systems. That’s absolutely NOT true!

But I have a hunch I’m not the only one who has dumped out a plastic tub system, only to find a congealed mass of sludge that looks something like this:

This is what happens in a system without sufficient air flow (not to mention drainage)! Unfortunately, these are exactly the sorts of systems that new vermicomposters typically start with.

When You Optimize the Process You Optimize the Results!

(You also optimize the experience!)

Plain and simple – it’s a lot more fun when vermicomposting works (and works well)!

With an Urban Worm Bag you can process more of your kitchen scraps, converting them into high quality vermicompost, faster!

And let’s face it…as “fun” as the vermicomposting process can be (at the best of times), at the end of the day, most of us are after the end products…

The beautiful, rich “black gold”…

…which helps us grow BIG healthy plants

…and heaps of our own nutritious “organic” produce!


1) What Kind of Worms Should I Use in an Urban Worm Bag?

Red Worms (Eisenia fetida/andrei) would be my #1 recommendation – and really that holds true for pretty well any vermicomposting system. They are so versatile, tolerant of awide range of conditions, and easy to work with that it’s tough to go wrong. That being said, most other real composting worms should also do well in UWBs. In fact, notorious roamers like Blue Worms (Perionyx sp) – which can process wastes at an incredible rate under the right conditions – can be really well suited for bag systems like this, since it is a lot more difficult for them to escape (than from a regular bin).

As for European Nightcrawlers, the jury is still out (since they tend not to be well-suited for Worm Inns) – but given the greatly improved moisture-retention in Urban Worm Bags, I suspect they will actually do very well (and I am working closely with someone who is actually testing them out as I write this)

2) What Quantity of Worms Do I Need?

I myself often recommend the “worm-rich material” stocking method – that is to say that I recommend transferring worm-rich material from successful active systems over to brand new systems as much as possible. This is much more of a “natural” approach, and it allows the population to find its own equilibrium over time. These worms are adapted for life in rapidly-changing environments, so when they have a great habitat, favorable conditions, food, and plenty of room to spread out, they tend to reproduce like gangbusters – and you end up with a big population of worms very well adapted for the environment they are in.

That being said (lol)…I still very much support the “pounds” and “counts” type of worm buying/stocking approach. The Urban Worm Bag is a big system, so it could definitely handle more than a pound of worms no problem (but anything above 5 lb would be overkill – maybe literally).

3) So How Big IS the UWB Anyway?

Here are the numbers straight from Steve:

Width (including frame): 26 3/4″ (68cm)
Length: (including frame): 26 3/4″ (68cm)

NOTE: I actually measured the L/W of my UWB stand as 26 1/4″

Height: (including frame):30 ΒΌ in (77cm)

Volume at Max Load:5.3 cubic ft (122 liters)

Bottom-line: This is a sizable worm bin, very close to the same size as a Worm Inn Mega (but as mentioned earlier, it is shallower and wider). Be sure to test the footprint size in your home/apartment if you are limited for space. I was quite surprised by how big it is.

4) How Much Waste Can This Beast Process?

How long is a piece of string?

Like a lot of things in vermicomposting, the answer is very much “it depends“! There are many factors that come into play here: temperature, moisture content, quantity of worms, age of system, experience level of the vermicomposter, types of foods being added, food optimization strategies being used.

Can it process a lot more than your run-of-the-mill plastic worm tub (or a Worm Factory 360 for that matter)? ABSOLUTELY!

The key (as with any system) is to focus on helping the worms (and microbes) to the best of your ability and then let nature do the rest!

I am closely monitoring the quantity of food scraps going into my own UWB, so be sure to follow my posts on the blog to learn more about this!

5) Is The Urban Worm Bag Available Outside of USA?

YES– but please do NOT order from this page if you are ouside U.S.A.

If you want to inquire about pricing to have an UWB shipped to Canada or elsewhere in the world, simply drop me a line (and put “UWB” in your subject line) and I will help you get things sorted out!

6) Can The Urban Worm Bag Be Used Outdoors?

Over the years I’ve often referred to the Worm Inn as a sort of “ultimate” indoor home vermicomposting system – because it helps you avoid many of the hassles new vermicomposters often deal with. I have the exact same feeling about the Urban Worm Bag – but even more so because of the design improvements, and just how darn nice looking the thing is (especially compared to many other indoor worm bins).

This is a bin that is just begging to be used in a climate controlled-environment so that you can consistently enjoy the real benefits of vermicomposting.

Can it be used outside? Sure – and there’s a good chance it will be easier to manage than a plastic bin, and last longer than a Worm Inn. But you are still going to be faced with challenging times, especially if you are in a location with really extreme weather (hot, cold, dry, wet…or all of them!! lol)

If you do use it outside, do your best to keep it protected from sunlight, and the elements in general. Also be sure to monitor temperatures in the system very closely during hot and cold weather.

7) What Sort of Support Do You Offer?

If you order an UWB from “Compost Guy” (that’s me – lol) you are in very good hands indeed. Steve and I have a very similar approach to taking care of customers, so in a sense it is like a DOUBLE support guarantee. I will periodically check in on RWC UWB owners to see how they are coming along – and you are more than welcome to email me anytime with questions or concerns!

Steve has got the product quality side of things totally covered. UWBs have excellent construction but if you happen to encounter any defects etc just fire me an email, I will let him know, and we will do our best to fix the problem.

Those who are interested in more of an in-depth UWB education may be interested in my UWB video series (once released). For a limited time it will actually be included as a free (future) upgrade for all those who order one or more UWB(s).

8) Can I Order My UWB With Worms?

At this time I don’t offer UWB + worms package deals – but here is the thing…my BIG recommendation is to start by getting the system up and running without worms. Shipping is stressful enough for the worms as it is. Last thing they need is to then wait around for you to get your UWB set up and ready to go.

You don’t need to be completely set up before ordering worms, but I at least recommend waiting until the UWB has arrived (or when it is expected to arrive very soon). Setting up the habitat and letting it “age” a bit helps to kickstart the microbial community, which will help the worms feel more “at home”.

9) What Is “Flow-Through Vermicomposting”?

Composting worms, such as Red Worms (Eisenia fetida/andrei) are what’s known as “epigeic” earthworms. This is just a fancy way of saying they live close to – or in fact, usually above – the soil surface (typically in deposits of rich organic matter). As fresher food materials are added on top or to the side the worms tend to move away from the processed material (containing a lot of their “wastes”, known as castings) and towards the better food source.

In a “flow-through” (often called “continuous flow”) system like a Worm Inn or Urban Worm Bag, food (and bedding) is deposited on top, and as the level in the system rises over time most of the worms end up concentrated in the upper half, while finished vermicompost (rich in castings) – usually with far fewer worms – ends up near the bottom.

Once the system has been “primed” (reached the point of being ready for first harvest), harvesting can then take place over and over again (periodically) without needing to dump out the contents and start over again (as is usually the case with bin systems).

Flow-through systems tend to produce higher quality vermicompost more quickly than typical bin systems (especially plastic bin systems).

1 Urban Worm Bag (USA)
(with Metal Stand, Free Shipping & Support)


2 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


3 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


6 Urban Worm Bags (USA)
(with Metal Stands, Free Shipping & Support)


If you have any unanswered questions about the UWB, don’t hesitate to post them below!


    • Ansel Wade
    • July 22, 2018

    How many Adult Euro Crawlers can one harvest from UWB after it is all setup and going, say after 6 months assuming you started 500 bait size adults? Followed guidelines and had good conditions.

    Understand there are variables so I’m just looking for approximate number of harvestable 3” fishing worms can one expect to be in the bag after 6 months?


    • Bentley
    • July 22, 2018

    Hi Ansel – that is a very difficult question to answer, especially given how new the Urban Worm Bag system is. The good news – in my opinion anyway – is that a UWB should be much better suited for Euros than one of the more breathable bag systems (eg Worm Inn) – but what sort of population growth you can expect in 6 months is virtually impossible to predict without actually putting it to the test. There are just too many factors that can have a major impact on the success of the system. If you are really serious about raising Euros, I highly recommend you not rely on one system, or leave things as-is for 6 months. Let the breeders do their thing for a while then move them to another new system so as to maximize their breeding potential.

    This does sound like a fun potential experiment, though. There is a decent chance I will try Euros instead of Red Worms for my next UWB set-up, and I think it would be interesting to see how fast a population of them will grow in this system.

    If you already have some results of your own, please be sure to share them here! Likely many others who will be interested in the potential of raising Euros in UWBs.

    • mike
    • October 6, 2018

    I purchased the urban worm bag a month ago. I must say I am impressed.

    A brief summary of my worm composting:

    I started because my outdoor garden compost pile had to be stopped due to construction. My winter compost was a frozen block. So I threw the frozen pile in the bottom of a new raised bed garden and covered it with dirt.

    I read the book Worms Eat My Garbage from the library, and like many others I got out an old storage tub and started.

    2lbs of red worms from online supplier. shredded newspaper, about 2 cu ft.
    Quickly found that moisture and fruit flies( Doing this on my sun porch) were the main problems.
    After 3 months I did an inventory and still had worms and decided to control moisture by switching to fabric grow pots (I put the old tub with old grow media under a tree in backyard to preserve missed worms and capsules of babies. Added a new smaller compost bag with 250 red euro crawlers, for fun and knowledge.

    After a month I found that my moisture problem had gone to the dry side, literally no moisture next to fabric sides. I found the Urban worm Bag online.
    version 1.0 on sale. and figured I am in deep so why not try a professional rig? How big is it? I combined all 3 containers in to the UWB oldest in first crawers in second and reds on top. This almost filled all 5 cu ft of the bag, the old stuf had been outside in the rain and was saturated the frame held, like I said. I was impressed!
    So the moisture excess from the old stuff bled out the bottom zipper in to my water heater drip pan, all good. Moisture problem stabilized and I began freezing newspaper wrapped “food” in ziplock bags and fruit flies got better.(Also helps control heat in summer and compost cooking). By the way balsamic vinegar is a great attractor for traps for fruit flies.

    I will harvest the old original bin compost , out the bottom zippered door, on the local first day of frost to make way for winter composting.


    • Crystal
    • March 29, 2019

    How do you continuously harvest from the bottom without having everything fall through?

    • Bentley
    • April 4, 2019

    Hi Crystal – early on the materials are loose and much more likely to fall out (if the bottom was opened) but once the vermicompost starts to accumulate it forms to the shape of the bin. You actually need to scrape it out – so it’s not just going to fall out. One exception may be African Nightcrawler castings – they tend to be very granular and not as ideal in a flow through system (will fall out more readily).

    • karen cooper
    • May 9, 2019

    Bentley That was my question to, about harvesting from the bottom. I didn’t read all the directions about this bag before I purchased it, so I didn’t realize you needed to have it indoors.. That may not work for me, the garage is kind of hot and I have a unfinished shop but that seems hot also. I live on the Oregon coast and usually the weather is pleasant, today its 90!! I hope that is not going to be the usual temps out here. So where would you advise placing the UWB in my situation? I though about having it under some Doug Fir trees that is a shaded area.

    • Bentley
    • May 21, 2019

    Sorry Karen – just seeing this now. Yeah, I certainly recommend using an UWB indoors if at all possible since it will likely extend the life of the bag, and make it much easier to control conditions in the system. That being said, if you DO need to keep it outside, a well sheltered location (as you’ve suggested) should be ok. I’d still be pretty concerned about heavy rains – but overall your location is definitely better than many for outdoor vermicomposting!

Leave a Reply

Your email address will not be published. Required fields are marked *

Help ‘Spread the Worm’ and Earn!

* Get My Free Worm Business Starter Pack *

Password Reset
Please enter your e-mail address. You will receive a new password via e-mail.