Worm farming and composting 101
Composting worms (Different to earth worms) live the top layer of soil (or rather they live in the top layer of decomposing organic matter) so man-made products (compost bins and worm farms) are designed differently.
I have been trying to crack worm farming for a few years now (to provide all the decomposition for ALL my kitchen waste..meat dairy, citrus, onion as well as the normally accepted worm foods) and I have cracked it. It simply requires a spot that will stay moderately warm in winter and cool in summer and never in the sun (for our climate with average winter days of 16c). It also requires you have a large enough worm farm so you are never overloading the system. I have the luxury of space under my house in the shade (I've literally cooked worms before in the heat in the sun (they like temperatures between 10-22c). I had 2 of the worm cafes from Bunnings which don't go anyway near providing enough decomposition for a family of 3. They are great for kids so maybe have one for the kids to learn with (they are a great height for kids) but they are not effective tools.
I saw a few people making worm farms from wheelie bins so I made my own. You can buy the complete worm farm including the wheelie bin or just kits from a variety of suppliers including ourselves. They work very well. We have 2 which is enough to get us through winter (when production is much slower) and more than enough for summer.
Composting can be done in 2 ways.
The first is hot composting (thermophilic).
This requires around 1m3 of organic matter to really get the heat up.
The heat kills pathogens and breaks down organic matter very quickly (all the organic matter needs to be around 1cm thick or thinner and the shorter the better. Small thin sticks (like 15-20cm) are ok in moderation but wood mulch is more suitable. Branches are not suitable. After you turn the pile about 9 times (you can do it every other day or once a week) it's pretty much ready. It's not what you would call soil but more looks like very broken down mulch that is quite dark. There is usually not much worm activity in this process as the pile has been too hot for worms (or any animal) other than the edges. Once the pile stops generating heat the worms will move in and make vermicompost. That is very much a second step in the process.
The second way is cold composting (or a rat party as I like to call it..sometimes snakes come too to party with the rats).
That involves randomly piling stuff up and hoping nature does it's the thing..unfortunately nature generally doesn't pile up stuff often (with the exception of natural disasters) so the pile often goes anaerobic which causes the pile to release methane and bad bacteria will start to breed. When you use the compost it may have pathogens (which may kill your plants (yes I did it to an entire weeks worth of commercial nursery seedlings and cried) and weed seeds. Over time the worms will move in (if it’s not putrid) and sort things out.
Worm farming is a bit like cold composting but you just need to add scraps to the farm once the worms have eaten the last lot and are ready for seconds. Add too much and you are back to cold composting and I’ve experienced maggots moving in, putrid spots and the worms moving out.
As mentioned before it’s about scale. If your worm farm is too full then you need to start another one until you have the space to meet your needs.
With the wheelie bin, the top is large enough that I add my scraps to one corner, I bury it (to hide it from flies) and I add an equal amount (to that of the scraps) of sugarcane mulch. I’ve found that worms really enjoy the presence of sugarcane mulch. As there is sugar in it bacteria like to build on it and in turn the worm eat them too. I rotate the scrap holes around the edges of the bin and finish the last one in the middle before repeating (Sort of like the number 5 pattern on a dice). By the time a rotate back to the first hole it is usually 90% compost.
What to do with your weeds/grass etc.
Yes well you can’t really add a lot of weeds to your worm farm like you can in compost.
My solution is I pull weeds and turn them upside-down and leave them in situ to turn back to mulch.
Other hardier weeds can be hung in trees to dry and die (then returned to the soil). Really bad ones can be put on concrete on a hot day.
I have some really bad vines at the moment that dominate half my property and have bulbs that look like, and can be the size of a medium size beetroot.
They are very hard to kill. I will build a solar dehydrator to basically cook these weeds so I can put them back into the soil.
On that tangent..now you have those very dry weeds, you can put those in the worm farm as your carbon elements in lew of the sugar cane (or along with sugarcane)
I like both composting and worm farming and you can do both. If you want to in-fact speed up the process of worm farming, you can make a big pile of compost and then use the compost as the feedstock for the worm farm (and omit food scraps).
My feeling with that is that when you use the compost in the soil, the compost worms come anyway and have their own party.
The reality is that building a large compost pile takes a lot of work and time. You can build up the materials over a long period to make the pile or buy material in. This days I usually only make compost piles for workshops and demos. I do like to make one pile each year to use for a potting mix medium but it’s a lot of compost for most people. I will bag it up and keep it under the house to mature. I allow a small gap at the top (I don’t seal it properly) for worms to move in and out and to allow air. Somehow, worm eggs always end up in each bag.
I think worm farming works for most people the best and especially in urban/suburben environments as it is a quick process every day to deal with the scraps. I put a large container of sugarcane mulch next to the worm farm, open the lid of the worm farm, make a small hole, throw in the scraps and add the mulch…done.
It’s really is a two minute job.
We are selling our bins and kits on gumtree and also through our website. If you want to make your own then there are lots of Ideas and videos on you tube.
If you work with a school I’d really love to help get lots of these bins to you.