As a gardener in Denver I've heard of worm castings as a potential soil supplement/fertilizer before. I've been composting with a traditional aerobic/thermophilic system for a while. The research I've done recently is that worm castings or vermicompost is a much better fertilizer than traditional compost:
- more nitrogen from the inputs stick around to the output
- the nutrients plants need are more easily consumed by plants
- there's more of the beneficial fungus and bacteria you need to create high quality soil
But...where can you get worm castings in Denver? And what does it really include and how much is it?
Worm Castings on Craigslist?
Searching craigslist for worm castings, vermicompost or other keywords often finds vendors who might have retail locations, just do delivery, or who will meet you somewhere. The sellers seem to come and go. Big Red Worms is one commercial name that has castings available at $1.50 per pound for small orders or $1.25 per pound for orders over 100 pounds. It seems the marijuana industry is a source of some worm castings, either from grow operations tossing out their growing medium or vendors who focus on that industry. One example from the city of Pueblo is Colorado Weed Company's build your blend can be pure worm castings for $1.10 a pound of worm castings.
Rocky Mountain Worm Company
The Rocky Mountain Worm Company is located in Colorado Springs. They sell worm castings on High Yield Organics.net at a price of $6.00 for 1 pound of worm castings. They are very clear that their castings are 100% castings and do not contain other compost material from a bin. You could of course mix their castings with compost to end up with something that resembles the contents and price point of other vendors.
Located on the Northwest edge of Denver, A.B.C. composting doesn't sell castings, but they do sell worms and other related products like bins.
Root Naturally - Organic Gardening
The folks at Root Naturally provide organic gardening products in general, including worm castings. They offer appointment only pickup of some products at their Denver location. 30 pounds of worm castings are $16.50 ($0.55 per pound) or 2000 pounds for $650 ($0.32 per pound).
Colorado Worm Man
John Anderson is the Colorado Worm Man and was the first person who ever showed me an active worm bin at a fall harvest festival for Grant Family Farms in about 2012. He does not seem to sell worm castings, but
Innovative Organics on Morrison Road
The folks at Innovative Organics have just a bit of information on their website and I've contacted them to see about getting some worm castings.
Dirt Dynasty - Mail Order
The pun-filled website of Dirt Dynasty at buywormcastings.com offers Vermicompost in 20 pound bags for $15 ($0.75 per pound).
Blue Collar Worms - Fort Collins
A short drive north to Fort Collins will get you some worm castings from Blue Collar Worms who does local pickup only.
Know of some other options? Please let me know and I will update this page.