Question from Bruce:
I would like to help a local animal shelter who has a problem with too
much dog poop by using a worm bin to decompose the dog poop and
creating fertilizer that could be sold to help fund the shelter. Can
this be done?
I have read that you can only use the dog fertilizer for flowers not
food related plants correct? how long do you think it would take to
start harvesting fertilizer for sale?
The short answer is that, YES, dog poop can certainly be processed by composting worms. My brother-in-law tosses most of his dop poop (during warmer times of the year) in a basic backyard composter containing Red Worms, and they readily convert it into rich compost.
Would I suggest doing this on a larger scale and then selling the compost to the public? Not likely. Or at least not without a lot more steps/processes in place.
Composting worms have been found (in multiple academic studies) capable of destroying human pathogens, so there is a reasonable chance you could end up with a fairly safe end product simply by vermicomposting the material. The thing is, though – would you really want to take a chance? Even with a specialized, professional flow-through system and a high density of worms, there is no guarantee that all the waste materials will end up passing through the digestive system of the worms.
And then there is the public perception – perhaps the biggest hurdle of all. Regardless of what these worms are capable of, people just tend to think of any type of animal waste product as “dangerous” – largely thanks to the over-hyped media coverage of e-coli and salmonella outbreaks etc.
If you were really serious about this, and had the resources available, my recommendation would be to mix with dog poop with lots of absorbent, carbon-rich bedding materials and hot compost it for at least a couple of weeks before feeding it to the worms. The retention time in the vermicomposting system should be at least 60 days, especially if you plan to use anything other than a professional grade flow-through bed. Upon completion of the process, the compost would absolutely need to be tested on a regular basis to ensure that no disease organisms were present.
I still think it could be a worthwhile project to help the shelter turn their poop into compost – don’t get me wrong. You might simply focus on using the compost on their property instead of selling it. As alluded to above, you will need some larger systems, though – not just a few “worm bins”. A low-tech approach might simply involve heaping the poop and bedding up to the point of initiating the hot composting process – and then perhaps spreading the pre-composted material out into windrows for the worms. Operating at that level (with those volumes) I’m sure you would need to look into local regulations on manure handling, however. Bare minimum, I’m sure all this would at least need to be done up on a concrete pad of some sort. You would also need to make sure there was no run-off into the surrounding environment.
A contained system – something similar in design to a composting toilet, for example, might be one alternative that would involve less red tape from your local governing bodies. But it doesn’t sound as though this is a project with much in the way of funding, so you’d have to decide if this was feasible.
Bottom-line, I’m definitely not trying to be a wet blanket here (lol), but this is definitely the sort of project that should involve a LOT of due diligence if you plan to start on a large scale and/or get the public involved.
Hope this helps! Good luck.