It ain’t just worms in there!
If there is one concept that will help you understand your worm bin better (and, how to care for it better), it is this: your worms are not the only living thing in your vermicompost bin. Your Red Wigglers might be the most visible organism, but they are simply the benefactors of the work done by a lot (millions) of other equally important composters whose work goes unnoticed to the human eye.
The vermicomposting mainstage
Composting worms put the vermi in vermicomposting. Vermi is a latin word for worm (you’ll never look at vermicelli the same way). Vermicomposting gives us a unique product that is quite different from hot compost. It gives us vermicast: worm castings, or worm poop. The worm’s unique digestive enzymes (among other things) help to create a stable manure, rich in nutrients, that doesn’t require any aging and can, therefore, be used immediately and directly on plants. The benefits of vermicast are many; that’s the topic of a future post.
Worms occupy center stage in vermicomposting, taking all the credit for turning your food waste into nutrient-rich organic fertilizer. However, there is an entire crew working behind the scenes that allow the worms to do what they are doing. In her excellent, short primer on vermicomposting, Worms Eat My Garbage, vermicomposting pioneer Mary Appelhof calls this behind-the-scenes cast of invisible-to-the-naked-eye microbes “composting associates.” Frankly, the show can’t go on without them, regardless of how many star worm performers you have on stage.
The real workhorses of the vermicompost bin
Generally, the term microbes refers to the microscopic team of protozoa, rotifers, and nematodes that are the first ones to the buffet, before the worms even think about eating that apple core you threw in your bin. This team of microbes, along with moulds (fungi) and other tiny critters swarm that apple core and begin feasting on it, breaking it down quickly and efficiently, albeit microscopically. Worms, in turn, eat the microbes.
Think about it: worms don’t have teeth, and their mouth is smaller than the tip of needle, how could they eat that apple core? Their mouth is more like a vacuum cleaner hose, sucking up small microbes and bits of food that have become small enough through the work of the composting associates. The image of worms munching their way through apples is simply not accurate: they can’t do it without their friends! Without their composting associates, worms simply do not have the means to ingest the food all around them. It would be literally comparable to you trying to eat an apple through a straw: it ain’t happenin’!
1000 worms, zero composting potential
If you’ve done any internet research on vermicomposting, you’ve likely found that most websites recommend starting a small worm with one pound of worms (which, is roughly one thousand adult Red Wiggler worms). This is a great suggestion, BUT ONLY as long as those worms come shipped with their composting associates.
It is common practice for large-scale worm farmers to ship a pound of adult worms in peat moss, coconut coir, or some other sterile bedding that does not have supporting microbial community (not all large farms do this: there are definitely high quality, large scale worm farms). What often happens in this situation is that, once you receive your worms, they essentially starve to death because the bedding did not include any microbes to break down the food you put in your bin. The worms are left to try to process large particles (eating an apple through a straw) without any success. While your new composting bin will eventually become inoculated with microbes (naturally occuring on food wastes, in the air), it typically doesn’t happen quickly enough to avoid a large die-off of worms. It’s worth asking your seller about the bedding material that the worms come in, regardless of if you’re buying your worms at a farmer’s market or are getting them shipped through the mail.
So, how many worms do I need?
The answer to this depends on a variety of factors: bin size, feedstock volume, feedstock type, vermicast production, etc. Another post will be dedicated to giving guidelines to answering that question. The reality is that you can start a worm farm with two worms, if you’re patient and attentive to your bin conditions. Many people become obsessed with starting with exactly one pound of worms, or exactly one thousand worms: don’t worry, the population will grow…quickly! If you can ensure that wherever you buy your worms from includes some of the worm’s living habitat that they were raised in, this will help ensure that you’re getting some microscopic composting associates as well. This is a much greater factor in ensuring the long term composting potential of your worm system than the amount of worms that you start with.