It’s been quite some time since I responded to any reader questions here (hope to start doing so more often), so I was inspired to do so when I came across this interesting question from Anna:
I’m interested in constructing an outdoor windrow or bin for
my worms this summer but am afraid that the mole (or it’s relatives)
who was feasting in my cold compost pile this summer will come back
for a repeat performance. I’ve considered hardware cloth on the
bottom and sides of the enclosure but am afraid this will not stop the
I’d also like to add that I really love the content on your site.
I’ve read through my library system’s entire list of books on
vermiculture and still feel like I know nothing. Your site has helped
plug some of the massive holes in my worm-knowledge.
Thanks for the question! While I am happy to report that I’ve never personally dealt with moles myself, I’ve certainly heard from vermicomposters who have. Interestingly enough, a good worm farming friend of mine recently sent me an email informing me that moles were wreaking havoc on his outdoor composting worm population (worms he’s been raising trouble-free for years I might add). So, needless to say, I understand how much of a threat these pesky varmints can be in some locations.
I think you are on the right track in terms of preventing moles from feeding on your worm herd. You mentioned potentially setting up a windrow or bin. Of the two, it’s safe to say that an enclosed bin of some sort will certainly provide the best protection. To be totally safe, you may want to put your bin/box up on blocks/legs of some sort, or place it on a concrete/asphalt surface (ie keep in on a patio, driveway etc) – although, I’m sure you’d be fine with a rugged plastic bin sitting directly on the lawn, assuming it was enclosed at the bottom (other than some drain holes).
If you want to have some sort of in-ground bed, you should probably either set a solid bin in the ground or plan to put a very serious effort into lining the bottom of your bed. I would think that a double layer of heavy duty landscape cloth and perhaps a layer of wire mesh would do the trick.
I have read that various types of plants can deter moles – two examples are Castor Bean (Ricinus sp) and the “Mole Plant” (Euphorbia lathyris). Be sure to check out this article to learn more: Companion Planting: Organic Pest Control Against Moles.
I’ve read that other natural repellents, such as onions, garlic, peppermint and hot peppers can work as well.
Alternatively, there are also commercially available repellent mixtures and even electronic devices designed to get rid of moles, although I have no idea if any of these are effective.
Anyway – best of luck keeping your mole(s) at bay!