Mushy newspaper clumps in worm bin
Here is a question from Maria:
I love your blog, but haven’t seen this topic covered. I’m
new to worm composting and I’m working on balancing my bedding/food
ratio. After about 8 weeks with my first batch of worms, I had lots
of mushy/soggy newspaper clumps, some compost and some undigested
food, even after I stopped adding food for the last 2 weeks. Any
suggestions for getting rid of these newspaper clumps? Should just
use less bedding? Or would only adding bedding that’s dry do the
To be totally honest, eight weeks is still a relatively short period of time in the life of a worm bin – especially the first eight weeks. Carbon-rich materials like newsprint also take quite a bit longer to break down than most food wastes. There is no doubt that the worms would eventually convert pretty well everything into castings if you left the bin long enough, but this could take quite some time.
Unfortunately, as useful as an enclosed ‘bin’ type of system is for indoor vermicomposting, they are not really the ideal systems for quickly producing good quality vermicompost/castings. You need a lot of air flow, which plastic bins generally don’t provide (in comparison to open systems and various ‘flow-through’ designs). As such, there tend to be lots of zones bordering on (or even completely) anaerobic – i.e. where oxygen is absent. Unless you have good drainage out the bottom, it is almost inevitable that you will have a fair amount of undigested material down in the bottom of the bin, regardless of how long you wait (unless you periodically mix the contents of the bin).
Something else to remember is Carbon-to-Nitrogen ratio. Generally it is the food waste that provides the nitrogen necessary to speed up decomposition of the C-rich materials like bedding. In other words, by completely stopping your feeding for a couple weeks (which is in fact not a bad thing to do every now and again) you may have actually slowed down the process somewhat.
I always recommend adding dry bedding to a worm bin, since one of the key advantages of adding bedding is that it helps to absorb excess moisture (thereby helping to avoid anaerobic conditions). Adding it dry also helps to avoid the clumping you are talking about. Aside from that, I would also recomend breaking up the clumps and mixing them around (just do it carefully, so you don’t disturb the worms too much). The more surface area that is available for microbial colonization and worm grazing, the more readily any material is going to break down.
One final thing to mention – the density of worms in the system will obviously play a major role as well. I have had really high densities of worms in a relatively small system and it was amazing to see how quickly they seemed to plow through everything.
Anyway – hope this helps!