1) As for salts in the worm castings, I would guess that it would tend to depend to a large extent on what you’re feeding to the compost worms. When I’ve added dinner scraps to my red wiggler worm bins, I’ve often thought that I’m probably adding way more salt than would be present in raw vegetables or other food prep scraps. At some point soon I plan to do some semi-scientific tests on plant germination and growth using various concentrations of worm castings / vermicompost vs. traditional “hot” compost and other soil blends.

2) I agree, composting with worms does not kill seeds like hot composting can (if done correctly). On the contrary, I think a worm bin provides pretty ideal conditions for seeds to sprout in. Fortunately, it’s generally only vegetable seeds that are mixed with the compost, no noxious weed seeds. When I sell worm castings, I screen them with a 1/8″ screen to exclude seeds and other bits. I thought they provided good size comparison in the photos, though.

A couple of things:

1. I sent my castings in to get tested at a soil lab, and they came back relatively high in salts. So I would always use castings to amend soil, and not plant in it directly.

2. The seeds you see in the pictures are not killed by vermicomposting–the temperature simply doesn’t get that high. I’ve had seeds sprout in houseplants I added vermicompost to.

Thanks for the book recommendation, I’ll have to check it out!

Dan Moore

When you first get your compost worms set up, feed them very sparingly for the first couple of weeks. Overfeeding is probably the #1 cause of worm bin failure.

Once your compost worm bin is going, storing the food scraps in a closed container on your kitchen counter for a couple days at a time is fine. Many people find that an old cooking pot with a lid works very well — something that’s large enough to conveniently hold your scraps, and easy to open with one hand. You want to make it as easy as possible to add food scraps as you’re cooking or cleaning up.

One option would be to ask a local convenience store or other place that sells newspapers if you can have their unsold papers. Once a paper is a day old, they just get recycled.

I’ve used chopped dry leaves with a lot of success (mixed with newspaper).

I think regular copier paper would probably be fine, also. Maybe give it a shot in 1/2 of your bin, so the worms can move to the other side if it doesn’t work out.

Thanks for any suggestions.

I don’t have a lot of experience with those fancy multi-level worm bins. As you can see above, I prefer a simple wood worm bin design. Sounds like things are going pretty well in yours, however.

From what you describe, I would guess that you’re feeding a bit too much for your worms. Many people cite 1/2 pound of food scraps for each 1 pound of worms per day, but I’d suggest something closer to 1/3 of a pound of food scraps per pound of worms, especially as you’re first getting started. It’s much better to underfeed slightly than to overfeed (creates smell, excess moisture, pests, and all sorts of problems). Underfeeding your worms will just make them grow a little slower.

I’d suggest being patient and feeding a little bit less right now. If that means throwing away some food scraps — so be it. You’ll be a lot more successful in the long run if you give the worms only as much as they can comfortably handle at any one time.

As for when to harvest, I’d wait until the bottom bin seem like it has almost no food scraps and very few worms. The idea behind those multi-level setups is that you’re not supposed to have to separate the worms out of the compost as you harvest. That’s one of the trickiest things for new worm keepers to get the hang of.

Have fun with it, and don’t hesitate to write again if you have questions!