A Guide to Simple Worm Farming Techniques
Even novice gardeners are aware of worms as a driving force in the garden, and this is especially so for those no-till beds so popular in permaculture plots. For most of us, it’s no great revelation that soil thick with worms is also likely to be thick with plant growth. The reasons are many, but in the most basic terms, earthworms are great for aerating soils and transforming organic material into fertile, microbially rich (and hygienically safe) castings.
While worms do inevitably show up where good soil and good eats combine, the keen agriculturist to both speeds up and fosters this process. There are many methods for doing so, from large-scale projects like pastures to raised garden beds in suburban lawns to high-speed vermicomposting boxes under the kitchen sink. And, like anything permaculture, these systems feed in perfectly to sustainable cycles, and once started, they are easy to replicate.
A Simple Indoor Vermicompost Project
I’ll go ahead and assume that today’s readers are do-it-yourself types, so I will breeze through mentioning that prefabricated worm bins are available for purchase (starting at about $100) and assume yours will be built at home. In this case, there are a few things to consider in constructing one: worms like it dark and cool, the juices will need to drain, they make composting much quicker (eating about half their body weight each day), composting worms are not just any old earthworms, they require rich surface matter on which to feed, and they multiply—figuratively—like rabbits.
With that in mind, the most basic indoor worm bin is to take a sealed container, like a plastic storage box, and fill the bottom with shredded paper and/or cardboard. The worms — red wigglers being the most common choice—can be mixed into the paper, and food scraps are just added atop this. A small improvement would be to create a drainage spout from which the worm “juices”, amazing fertilizer, can drip into another container, keeping the worms from drowning themselves. Then, the bin is just emptied when full and the process begun again with the existing worms.
• Note: As the worms multiply, it’s possible to halve the bunch (clew or clat) of worms to produce another worm bin or introduce them into the worm bucket in the garden (We’ll get there in a second). But, the worm population will multiply quickly.
Another worthwhile improvement would be to compartmentalize the container. A partition with a few holes drilled in it will essentially make two vermicomposting boxes out of one. This is advantageous because, once one side is full, you can begin filling the other half. Through the holes we’ve drilled, the worms will then migrate towards the food, making it much easier to remove the pure worm castings without having to contend with pulling out handfuls of worms and unprocessed veggie scraps.
This method is perfect for urban and rural settings alike, and it’ll function just fine under a kitchen sink, where the compost bin would likely have been anyway.
A Vermiculture Garden Project
While kitchen vermicomposting systems are great, some would say that having the whole set up outside, in the garden, is probably a more efficient choice. This way the worms can have freedom of movement, hopefully helping with the tilling while they do their real work: quickly converting organic matter into compost. Just as with composting directly in the garden, which feeds the plants when fertile liquids leach into the soil, a vermiculture garden bed, i.e. with a worm bucket, provides steady, effortless, natural fertilization.
Worm buckets, or towers, are also very simple to make. Firstly, they function best when the worm are allowed to freely roam in the garden (They’ll always come back to the bucket for the food), so it’s best to cut out the bottom of the bucket and/or drill several roughly 20mm holes around the bottom rim of the bucket. Then, the bottom third of the bucket should be buried, leaving the top sticking out vertically from the garden bed. Again, the process starts with shredded paper, worms mixed in, and rich organic material atop that. The bucket opening needs to be covered to keep out both rain and predators.
These work great because they are such an easy and efficient way of handling garden debris, including weeds and especially overripe fruit and veg. Eventually, each bed can have its own vermiculture system to handle the waste while producing super enhanced plant food.
Another popular and contained outdoor system is using recycled bathtubs as large vermicomposting bins, taking advantage of the already existing drain to handle the juices. In this instance, the tub bottom should be filled with a layer of gravel (or timber frame), topped with a wire screen then cover over with—in ascending order—dry bedding, manure and kitchen scraps. And, once again, the whole thing needs a lid.
A Pastoral Vermiculture Revolution
Lastly, there is the more revolutionary act of spreading worms throughout an entire expanse of land, anything from a kitchen garden to a broad-acre pasture. I first learned of this via Bill Mollison’s Global Gardener series from the early 90s. In the “Cool Climates” episode (start at about 17:40), he visits an old friend in Tasmania who has been farming worms — Alibophorus Calliginosa — on a large scale for years.
His method again was practical yet, somehow, progressive. He would dig patches from his areas heavily populated with worms (any topsoil dwelling species should work), and replant the patches every few meters over degraded pasturelands. He sprinkles the area with dolomite lime, which might be questionable with modern research, but the point is that the worms need rich organic matter—animal manure, rotting roots, grass clipping—to feed on. Whatever the case, over the next few years, the worms help to produce hectares of highly enriched soil, regenerating damaged pastures.
In other words, once those smaller worm farms are really producing, there is a very productive way of putting the expanded worm population—numbers should grow exponentially within a couple of months—to good use. With the worms then incorporated into our permaculture systems, handling the business of feeding and breeding themselves, the fertility and goodness naturally multiplies. Soils build up, are aerated, become richer in minerals, increase in beneficial microbial bacteria, and are ripe for low-maintenance cultivation.
Feature Image: Happy Tiger Worms (Courtesy of Timothy Musson)