When I was up in Fort Collins for the Rocky Mountain Compost School, some classmates and I were able to get a tour of the facility of John Anderson (aka, ‘The Worm Man’). I was able to snap a few photos, and you can see most of them below.
Here is a view of the entire Worm Man operation, including fridges, wormbulances, and windrows.
Windrow containing worms. Notice the carpet covering the windrow, and the bales of hay.
Carpet covers all Johns windrows, preventing light from entering and moisture and smells from leaving.
Protecting the windrows from freezing is key. John uses bales of hay to prevent the prevailing winds from stealing heat and moisture from the windrows.
Here is a better shot of a windrow with the carpet pulled back. John is using a pitchfork to move some of the bedding to better show the redworms.
On the right is a pile of bedding and worms, covered in carpet. I believe the left is an uncovered pile of bedding.
John uses fridges as a cheap, effective worm bin. They are almost water tight, insulate well, and hold a large number of worms.
Here are some happy happy worms in the bowels of one of the modified refrigerators.

Here is a fridge that John made early in his experimentation. You can see the plastic on the door was not removed, and it is starting to get squishy.

John hot composts a lot of his feedstock for the worms. He got these large square bins from an A/C company, and mounted them on an axis so he can rotate the compost.
Here you can see John rotating the tumbler, using rope and his truck. I wish I had gotten video!
John makes money selling castings as well as worms. He stores finished castings in these 55 gallon plastic drums.
This was a piece of old farm equipment that John had on his site. A classmate of mine is indicating how it could be used as a continuous flow harvester. You would scrape off the bottom of the worm bin periodicaly, getting most of the castings and few of the redworms.
John built a separator on an old gurney; here is his primary casting separation setup. Worms and castings and bedding are taken from the wheelbarrow and put into the upper end. The barrel is rotated and the worms and vermicompost fall to the lower end. Castings fall through the screen onto the tarp.

The back of the ever popular Wormbulance.
June 28th, 2009
Via the_worm_bin comes a great idea for physically separating the worms from their castings. Here’s the original post. Note, these are not my pictures, but rather are Jennifer’s:

Closeup of worm castings shaker from a laundry detergent bottle

Worm castings shaker from a laundry detergent bottle
December 26th, 2008
From the_worm_bin comes this interesting idea of creating seed balls with worm castings. I think it’s great because, in addition to all the benefits from seed balls (protecting the seeds from birds, letting the seeds that are appropriate for the given environment sprout, etc) you’re providing the plants with worm castings, a powerful fertilizer, to jump start their growth.
To go this route, start with heirloom veggies. There are lots of companies that sell heirloom seeds. I would make a mini worm bin when the tomatoes come in next summer. Feed several ripe tomatoes to the worms, then dry the castings and store for the next season. Make seed balls and replant in the spring.
I wonder what else the worms will leave behind? It should be a neat process and a cool way to save seeds.
Karon suggested this after several people mentioned that tomato plants were popping up in their worm bins. This also shows why vermicomposting weeds is a bad idea–worms just don’t break down all seeds. I’ve had other plants ‘volunteer’ from my worm castings, including pumpkins and melons.
November 21st, 2008
I’ve always been curious about the content of worm castings. I have seen and experienced anecdotal evidence that the castings I pull from the bottom of my bin are extremely good for the plants to which I apply it.
There are a number of pages with the mineral content of worm castings, including this one, this one and this one, but I wanted to know what my own castings contained. I don’t doubt that the contents of your bin are going to depend on what you put in it. For example, I’d expect eggshells in the feedstock to increase the calcium content, and crushing those eggshells would probably increase that further.
I decided to contact my local soil testing lab and see what their analysis found. I dug a worm castings from the bottom of my bin and sifted them to remove any large chunks of wood and undecomposed material. I let them dry for a night, placed them in a labeled plastic bag, and filled out a form specifying tests I wanted. I mailed the whole package off to the lab.
Six weeks later, after a phone call to remind the lab I was waiting for results, I received the analysis. Here are the comments from the soil lab:
pH, which was 7.9, was “sufficient for a soil amendment.” Most plants have a pH range they prefer.
Electrical conductivity or salts: “The salts are elevated, however this material can be safely used as a soil amendment if it is used at the recommended application rates.” They didn’t give me recommended application rates, however.
Lime estimate: low, which “indicates less than 1% CaCO3.”
Sodium adsorption ratio (SAR): “Low; sodium is not a problem.”
Everything else tested had “high” levels, including O.M. (Organic Matter), NO3-N (Nitrate-Nitrogen), P (Available Phosphorus), K (Available Potassium), Zn (Available Zinc), Fe (Available Iron), Mn (Available Manganese), and Cu (Available Copper).
Numbers (ppm) and such available in the Full Worm Casting Analysis Report.
November 12th, 2008