Last week we started talking about ‘worm farming systems’ and the basic requirements needed to keep a population of worms happy and healthy. With our overview out of the way, we can now start talking in more detail about different types of worm systems, starting with a look at what many would consider the simplest worm farming system – the ‘worm bin’.
I should warn all you expert vermicomposters out there that this week’s edition may seem a tad basic. That being said, in my humble opinion, it never hurts to get ‘back to basics’ periodically to help solidify your overall understanding of the field of vermicomposting.
As I’ve written in a previous newsletter (and in the manual), just because the worm bin is generally associated with beginners and small-scale vermicomposting as a whole, that doesn’t mean it’s not worthy of respect. In the words of Larry Martin – a well known worm farmer with well over 30 years of experience in the field – “The most difficult vermicomposting operation is the plastic classroom or home bin. It’s very unforgiving. I’ve always told folks, if they can do it in [a] plastic bin, they could run the largest vermicomposting operation in the world.” (excerpt from a Casting Call interview, Vol. 2, #4)
This is one of the reasons I ALWAYS recommend starting with small worm bins if you think you might be interested in getting into worm farming as a profession. There really is no better way to introduce yourself to the process of vermicomposting and determine if it’s really something you want to get more involved in.
The term ‘worm bin’ can be used to describe any number of different (smallish) containers set up for the purpose of housing/raising worms and (usually) for composting food wastes indoors. In its most common form, it is often some type of rectangular plastic bin with a lid and air holes – similar in size to a recycling box. Carbon-rich, absorbent bedding materials such as shredded newspaper are moistened and mixed with food waste, then composting worms such as Red Wigglers (Eisenia fetida) are added. This is of course a very basic description – we’ll take a closer look at my recommended set-up procedure in a minute.
I should mention that while there ARE various flow-through ‘worm bins’ (such as the ‘Worm Factory’) on the market, we’re going to include them as part of next week’s ‘flow-through vermicomposting systems’ discussion.
Last week I talked about the importance of establishing a worm-friendly ‘habitat’ prior to adding worms to a vermicomposting system. As such, I generally recommend that people (especially beginners) don’t add worms to a bin the same day they set it up. As I’ve pointed out many times, worms rely on the presence of a diverse microbial ecosystem in order to thrive. If you add them to a bin containing fresh paper and fruit/veggie waste, they won’t find the type of habitat they are used to and may attempt to escape as a result.
If you mix dry bedding materials with food waste in alternating layers (starting and ending with bedding), spray it down with some water, then let it sit for 5-7 days (longer would be fine too), you should have a fairly worm-friendly system ready to go. While your bin is aging it is a good idea to mix up the materials periodically to help distribute moisture evenly and determine if more water is needed.
I should also mention that just because you are ordering your worms and your bin at the same time (quite common), it doesn’t mean you can’t still create a worm habitat ahead of time. Simply follow the same procedure using a bucket or a Rubbermaid tub, then transfer this mix to your new worm bin when it arrives, along with the worms.
If you are looking to save some money when you first start out (worms are expensive enough as it is!), I’d highly recommend making your own worm bin. This can easily be accomplished using a basic Rubbermaid bin, or any other similar plastic container. Always keep the important worm requirements in mind when choosing a container. In a nutshell, for best results it should:
1) Be opaque to help maintain darkness,
2) Have a high surface-area-to-depth ratio and/or have lots of air holes to maintain adequate oxygen levels, and
3) Be able to maintain adequate moisture levels (certainly NOT a concern with most plastic tubs).
If one of your main interests is producing quality worm castings, then you will definitely want to make sure your bin provides adequate air flow – the mucky compost that (slowly) forms in the bottom of most sealed plastic systems probably isn’t exactly the “black gold” that most people envisioned when they started up their bin. 🙂
For best results in the castings-production department I would recommend using relatively shallow, uncovered ‘worm tray’ systems (basically a kitty litter box with worms/bedding in it), or one of the various ‘flow-through’ bins – which again, we’ll be discussing next week.
Plastic bins are very durable and are great for maintaining high moisture content, but the latter is definitely a double-edged sword. It is very easy to end up with too much liquid in the bottom of a plastic bin (obviously assuming there are no drainage holes), thus causing low oxygen conditions and impeding the formation of quality vermicompost. Building your own wooden worm bins/beds can be an excellent alternative. While wooden systems can often cost more to make than the ‘Rubbermaid’ variety, they offer a number of advantages.
Wood tends to ‘breathe’, unlike plastic, thus allowing more oxygen into the system and more moisture out. This can be particularly helpful if you bin is located outdoors in a hot, dry climate, since the ‘evaporative cooling’ effect will greatly help to moderate temperatures in the bin.
You will of course need to be much more attentive to the moisture levels in the bin, since it will lose water fairly quickly on hot sunny days (especially if there are spaces between your boards). I should mention that this tendency to ‘breathe’ also makes wooden systems another good option for castings production.
Wood also allows the would-be vermicomposter to get a little more creative with his/her worm bin design. Whether it’s simply creating a system with ideal dimensions (sometimes a challenge when buying plastic tubs), or putting together a beautifully finished piece of vermi-furniture, building your system with wood can definitely be worth the effort!
One other low-cost option you may want to explore is the use, or more accurately ‘re-use’ of various containers originally intended for other purposes. Old feeding troughs, milk crates, baskets, planters or even a beat-up pair of jeans (as I demonstrated with my “Creepy Pants Vermicomposter”) can be converted into a ‘worm bin’ quite easily. Again, it ALL comes down to keeping that list of worm requirements in mind at all times and not being afraid to think ‘outside the bin’, so to speak! 😉
Ok, well I think I’ve provided you with enough of an eyeful for one week.
Stay tuned for next week’s discussion of ‘flow-through vermicomposting systems’- should be interesting.