I wanted to do a series of posts on how I maintain my Urban Worm Bag (UWB). I set up this system in mid-October 2020 after years of using a similar Worm Inn system. My decision to purchase a UWB had to do with the size of the system. The Worm Inn I had set up was the original Worm Inn, not the Worm Inn Mega so it is a considerably smaller system. Since the COVID-19 pandemic forced me to be at home more, my family produced more scraps than the Worm Inn could reasonably handle. Since the Worm Inn Mega was no longer available at that time, I decided to go with the UWB. The system is the UWB version 2.0 and not the original UWB.
I have been using the UWB for roughly six months now and really enjoyed how well the system has performed. I have harvested vermicast multiple times over this period. Since the system has been running smoothly, I thought it would be good to show how a mature system operates.
When I started the system, the setup was similar to how I set up most systems. The basic set up has an initial layer of dry, absorbent cardboard on the bottom and then alternating layers of bedding material and food scraps. Then I add the last layer using the Starter Worm Mix. The Starter Worm Mix inoculates the system with beneficial microbes and worms to get the system off to a quick start.
One thing I noticed about the UWB was that it holds moisture quite well. Even the outer edges of the system stay moist which is quite different from a Worm Inn. I recommend adding a top layer of dry bedding with the UWB. I have found that this helps regulate the system from becoming too damp. Also, I keep the bottom zipper open which allows for the bottom section to dry out a bit.
I feed the system roughly 1 to 2 times per week. This is somewhat due to availability of scraps and how the system is handling the prior feeding. A typical feeding shown below contains roughly 3.5-4 pounds of scraps.
For feedings, I typically use frozen scraps and chop the scraps finely. This process allows for quicker decomposition and becomes available for the worms faster. Although I highly recommend freezing the scraps, chopping isn’t necessary. I also mix in some screenings from the previous harvest. This kickstarts the microbial activity for faster decomposition.
April 29th, 2021 Feeding
It has been about a week since the last feeding. To start the series, I decided to weigh the scraps that will be added. The weight came in at 4 pounds 6 ounces.
I dumped the frozen scraps into a 5 gallon bucket for chopping. I allow the scraps to thaw about an hour or so before chopping with an ice scraper. My preference is to have the scraps only partially thawed because less liquid is produced and certain foods like banana peels and celery chop up better when partially thawed and not fully thawed.
One benefit of using an ice scraper is that you don’t need to use a lot of power to chop the scraps. Just a little bit of force is required. In this partially thawed state, the scraps are almost like a paste and can be moved into the UWB easily.
Next, I added some oyster shell flour to the scraps and mixed it thoroughly. The oyster shell flour acts a grit and helps maintain the pH levels. There are other materials that can be used such as ground eggshells or quarry dust, but this is what I had available.
The image below shows that there is already a top layer of cardboard bedding. The scraps will placed on the top surface of the bedding. Also notice that the system is about 4 inches or so below the black upper material of the UWB. In total, there is about 6+ inches of available space for bedding and scraps. It may be hard to see but there are worms on the sides of the system. The only time this would concern me is if there were hundreds of worms on the sides attempting to escape.
The chopped up scraps were added to the top surface of the system. Just something to note here. I wouldn’t cover the entire surface in a tote system, but the UWB breathes much better than a tote and will have enough airflow to prevent the scraps from becoming anaerobic. The scraps were about an inch in depth.
Then I covered the scraps with some material from harvesting that didn’t make it through the 1/8″ screen. This bulky material is already inoculated with microbes and will help speed up the decomposition process.
Next, I covered the the remaining scraps with some additional bedding material. This material was already optimized a bit with some alfalfa meal, coffee grounds, and oyster shell flour.
Last, an additional layer of dry, shredded cardboard was added. In the UWB and tote systems, I find this layer helps with moisture. The dry material becomes somewhat damp as it absorbs the moisture in the system. It also acts a barrier for potential pests such as fruit flies and fungus gnats.
Stay tuned to see how the worms process this feeding.