A friend recently asked how to get started with worm farming and, honestly, I couldn’t answer, as my brother set it all up for me. If there’s a guy who knows a thing or two about worms, it’s him. Being knee-deep in worm muck is his happy place.
He helped me put together this handy how-to for anyone keen to get started. Be warned though – it’s addictive. Once you harvest that first batch of black gold, there’s no turning back, you’ll never throw your food waste in the bin again. Here we go…
What your worms will need
- Like us, worms need oxygen to breathe, which they do through their skin.
- Darkness. Too much exposure to light slows down the decomposition process; it might drive them away or even kill them.
- Organic waste (balanced between ‘greens’ such as fruit and vegetable waste and ‘browns’ such as egg cartons).
- A temperature of anywhere between 10 – 35 degrees celsius. They tolerate cold better than heat, so your bin should never be in direct sunlight.
Choosing a bin
A number of options are available — from fancy shop bought systems to a plastic tub with holes punched into the lid. Plastic bins are probably easiest and most convenient because they’re durable, lightweight and easy to come by (though try use food grade plastics to prevent chemicals leaching into your compost). One drawback of plastic — the air flow isn’t good so you’ll need to manage your feeding schedule carefully to prevent anaerobic conditions being created.
Wooden bins provide the best aeration for your system (again, look out for pressure/chemical treated woods). Other options such as cinder blocks or bricks work well too but are cumbersome and fairly permanent.
Setting up your bin
- Create a bedding of organic matter — torn up egg cartons, toilet rolls, shredded newspaper (avoid the glossy stuff) or store bought coconut coir. Soil directly from your garden will be too heavy for the worms and probably contaminate the bin.
- Add some food. You can include anything organic that will decompose — fruit and vegetable peels and scraps, egg shells, coffee grounds and tea bags. Don’t include meat, dairy or bones as this will attract pests.
- Let the bin stand for at least a week before introducing any worms.
- Start SLOW. People have a tendency to over feed in the beginning, but only add new food when most of the previous batch has been eaten. After a month or so you’ll get a feel for how quickly your worms can process waste.
- If you opt for plastic bins, a popular choice are stackable meat trays, as this allows you to grow your worm system as you go. Here’s how you do it:
- Start with three (same-sized) trays. The bottom one will be for collecting any liquid run-off that comes out your bin. You can install a tap to help remove it.
- The next level would be your feeding tray. This is where most of your worms will be, happily eating, growing and breeding.
- If you want, add a third tray on top. This acts as a lid to keep out light and a means of separating your worms from your compost when the middle tray is full. The middle and top tray should have holes (about 6-8mm) drilled into the base to allow the worms to migrate to the top tray when the middle one is full.
- Food waste releases moisture when it decomposes but a light sprinkle with a watering can will help ensure the entire bin is moist. But don’t over do it, you don’t want it soaked, as this will reduce oxygen in the system.
- Feeding: little and often is best. Anything from once a week to daily, depending on your level of involvement.
- Place the bin in a sheltered space, preferably covered, so it doesn’t get wet. Cover food scraps with shredded newspaper (hand-torn is fine); this helps keep fruit flies at bay.
- If you can, freeze your food scraps beforehand (allow to fully thaw before feeding); this will kill any fruit fly eggs and accelerate the decomposition process.
- If you add lots of egg shells, dry them out either in the sun or oven and crush them before adding. It’s not vital but will give your final product a better looking finish!
- Check up on them too often. Constant disturbances will slow down their eating habits
- Place in direct sun
- Feed too much citrus, as it’s too acidic
- Feed pineapple and papaya seeds, as they can kill your worms. Rather save these for your traditional compost pile.
- Peek in your bin regularly (but not everyday). You should see rotting food and lots of worms wriggling about. It should be moist, and there might be other little critters crawling around. Common bin friends are springtails, mites (only a problem in excessive numbers), spiders, woodlice, the odd slug, small (not large) beetles, and centipedes (these can prey on worms but shouldn’t be a problem if you spot just one or two).
- Your worm bin is healthy if there is no smelly odour
- Conversely, it’s unhealthy if it smells bad! In this case it’s probably been fed too much and has gone anaerobic. Stop feeding the bin. Remove any uneaten food and gently turn your bedding in a few spots, adding torn egg cartons to neutralise it. After a week or so your bin should return to normal.
Sourcing your worms
Most good nurseries stock them. A small bucket of just worms (ie no soil or bin) will set you back about R350. If you’re impatient to get started or have some cash to spare, you could buy a ready-to-go system – ie the worms, already in soil, in a worm bin. That’ll set you back anything from R1,200 to R2,000.
Or, simply google ‘worms for sale in South Africa’ — suppliers change their prices depending on availability, so shop around for the best prices.
Head over here for a step-by-step guide to hot composting. Here for the differences between a worm bin, a bokashi system and a regular compost bin. And here for a post on why composting is like therapy for me.