Worms. we love them and actually really need them and so, we foster them. Not the type that crawl under your skin (gross), although they’re probably playing an important role I just don’t know about. We’re talking about the types that live in our soils – keeping busy aerating and cycling nutrients making them more available to other members of the soil food web and to the precious plants which we happen to depend on for a good portion of our survival .
Did you know that…
In one worm, there is around 474, 075 million bacteria – wowzers. These bacteria do an incredibly important job – mainly making minerals available – more on this below.
When compared to the parent soil (the original soil), worm castings (the worm’s poo) have approximately:
- 7 times the available phosphorous
- 6 times the available nitrogen
- 3 times the available magnesium
- 2 times the available carbon
- 1.5 times the available calcium
(Both these facts are from ‘Earthworms in Australia’, David Murphy, pg 26)
The key word used above is ‘available’. The worms do not magic these minerals into existence, they were already present in these quantities, however the worms have changed their form by digesting them (which involves all that bacteria). This process makes them available to plants as the minerals have been changed from being an insoluble form to a plant-available soluble form.
So this is why people keep worm farms – the castings and diluted worm juice (the liquid that comes out of it) are an invaluable fertiliser for food crops. A quick and important note, worm farms can only house compost worms, not your common earth worm you see in the garden or lawn. Compost worms are red wrigglers and tiger worms – you can buy these from nurseries, but you can usually find them at your local school/community garden if you ask nicely. Do not put the common earth worm into a worm farm – they will die.
So what type of worm farm should you have? It all depends, where do you live, i.e. apartment or farm, do you have a big or small garden, do you have lots or only a small amount of of food scraps coming out of your kitchen? Here are some options for you to ponder…
The Wheelie Bin Worm Farm
CERES Community Environment Park in Melbourne make their own wheelie bin worm farm which can house thousands of worms and a whole lot of food scraps. The great thing about this design is that there quite easy to move, having wheels and all – so perfect for people who are renting or for the busy cafe/workplace who may need to move it around every now and then.
The Bathtub Worm Farm
The bathtub worm farm is a true beauty and, when designed properly, can double as a table for potting up or doing garden jobs on. A few years ago I worked with the Urban Bush Carpenters in Melbourne to build local NGO, Cultivating Community this fancy worm farm you can see above left for a community garden. As well as doubling as a table, you can also use the space below the bath as storage (as well as having a permanent bucket to capture any worm juice. You can see more info on this one at Urban Bush Carpenters
The Shop Version
Of course you can just go and buy a commercial worm farm from most nurseries or hardware shops, you can even add compost worms to a standard compost bin.
The Styrofoam Worm House
You make make your own worm farm from styrofoam boxes. Images from here and here
This version is a great way to start if you’re on a low budget as it’s free or very cheap to start. It simply operates on the same system of having layered boxes with holes in the bottom for drainage and for the worms to travel in between. The bottom box has no holes and captures all the worm juice for you to use later as a fertiliser (dilute it so it looks like the colour of weak tea) for the veggie patch.
The Worm Tower
We love this one as it’s integrated INTO your garden so the benefits for your food crops are immediate and fantastic. You can buy them commercially, but they’re so easy to make we think you should just do it that way. All you need is some large pipe (ideally no smaller than 200mm wide), a pot plant to fit on the top as a hat and a drill to put holes into it.
This is what it looks like once installed into your garden. Image from here
Drill a number of holes of various sizes that the worms can travel in and out of. Image from here
But will your worms run away? Not if you continue feeding them fresh food scraps, as long as you do this they’re not going anywhere. It’s a great system for the forgetful as you can’t kill your worms through neglect, they’ll simply leave and find food elsewhere.
There’s literally a type of worm farm for any context, this is just a taster. Have a fun time exploring the options, just make sure you get one, they’re the bomb.
Worm Resources
- Very Edible Gardens have written a great article about worms and their needs and products
- How to build a worm tower
Love this post. I’ve been talking to people about biiig worm farms, and was told of the ‘yogurt trick’… So apparently…you can inspire mass migrations of worms-from one water tank sized farm to it’s matching neighbor by waiting for a rainy night then painting yogurt around the rim of the empty farm. Then hide under a brolly with a torch and get ready to be grossed out by amazingness.
Wow – the yoghurt thing sounds like a darn fine party trick – thanks for the heads up!
We recently put in a worm tower and I love it (used to have one of the shop-bought layered ones before). In our old farm, most of the worms would die every summer as the farm overheated, even in the shade. Now the worms can go hide in the dirt and stay cool. It’s the best.
I need some worms to start a worm tower.
Where can I buy them in the Eastern Suburbs of Melbourne, e.g. from Ringwood to Lilydale?
Also where can I buy a worm tower from?
Thanks heaps for the information, with kind regards from,
Faye and Chris Potter
Great information. Luccky me I recently found your blog by accident (stumbleupon).
I have saved as a favorite for later!
I’m surprised by the claim that our ordinary garden-type earthworms will die in worm farm conditions. For the last two years we’ve grown veges in fifty ‘elevated’ 100 litre containers, with a ‘drain-pipe’ allowing excess water and nutrients to filter down into fifty buckets below these boxes. We’ve added common, ordinary earthworms to each box, as we’ve found them. To our surprise, most buckets have collected scores of healthy earthworms, which grow to astonishing size in these nutrient flows. Moreover the worms captive in these boxes are all healthy, large and active.
Given our experience, why do earthworms in commercial wormfarms die, when _ours_ are so healthy and large?
Hi Ozcan,
Very interesting to hear of your experiences – I haven’t got an amazing answer for you, sorry. I can speculate that your system is beautifully balanced, meaning the common earth worms can thrive as well as red wriggler/tiger worms, whereas others might simply be too ‘rich’. All I can say is, if it’s work great for you – keep doing it!
Here’s a great link that clarifies the differences of the worms we commonly use and run across… thought I’d share!
http://www.julieorrdesign.com/which-worms-are-best-for-composting/
Can I do a pipe worm farm with 100mm pipe in pots? I might only have 40-70mm.
Is it worthwhile?
Bit too skinny I reckon Matt. More likely to dry out and/or be too hot/cold. But also, if you bury most of it in the pot it might be worth a go. Just need to chop up fo0d scraps more and check on them more often.
I find all these articles about ‘the best woRN for you’ amusing in that there seem to be only red wigglers and tigers as choices. And they never discuss which one of
Those is better for
What application.
Hi Nikole,
Usually they’re always together. When you buy them from the ‘shop’ they’re always packaged together and when I take a look into people’s worm farms there are always both. I’m not aware that one is better than the other.
Woot, I will cetniarly put this to good use!
Do you have to place a protective barrier, such as chicken wire, under the worm tower, to prevent pests from invading and eating your worms?
If rodents are a problem you can use a bucket instead of a pipe. I’ve used a 20 litre bucket that I’ve drilled holes into – the holes are big enough for worms to come and go but not for any rodents. You could of course add some “vermin mesh” to the bottom of the pipe as well to do the same job :-).
Fantastic, love this article!