Last year, my wife persuaded me to start composting in the apartment. Composting is very useful and ecological for a variety of reasons. It keeps away your organic trash and puts it to good use, you have no bad scents coming from your trash can and in the end you will obtain good fertilizing liquid for your plants, as well as some extra quality soil. Once you go over the psychological barrier of having live worms in your apartment (don’t worry, they won’t get out of the box unless you make them to), you’re practically done.
Everyone can make their own composting box cheaply with a little effort. Once you decide on the size (depending on how much organic waste you produce – look this up on the Internet if you’re not sure), you can start. A rule of thumb would be about 40 liters for an average household of two persons. This will be enough for your composters (worms) to digest the trash and turn into soil. So, let’s begin:
Ingredients and tools:
- 1.5cm thick plywood (or chipboard): 43x50cm, 50x23cm, 40x23cm (2 pieces of each)
- Bolts for wood, I used 4.5cm long + some glue for wood
- A power drill with a small wood bit (optional) and a 20mm wood driver
- Some transparent wood primer, some sandpaper and a brush
- 2 hinges with bolts (should come with them, or get 12mm bolts for wood)
- Some plastic netting for your openings and a bit of glue
- Two pieces of wood to serve as legs (optional)
Time and cost:
wood – 4 pounds, hinges and bolts – 2 pounds, wood primer and brush – 4 pounds. Time used (in my case) was an hour to put it together and a few days to finish it up.
- After obtaining the wood, you can simply put the pieces together. Start from the base (43x50cm) and work your way up. Leave the top part aside at this point. Attach the sides to the bottom using some glue (to hold it at first and seal it well), and after that, using some bolts. I used a bolt approximately every 10cm apart for a secure connection. When connecting wood, you should use bolts which are 3 times as long as your wood is thick. Hence, for 15mm thick blocks, you should use 45mm bolts. To make threading the bolts in the wood easier, you can make small holes with a power drill and a small wood bit.
- Your worms will need good ventilation, so you should make holes in the box. You can provide adequate ventilation by making about 5-8 20mm (diameter) holes. Use a wood driver to make them. You should keep holes on different sides of the box (not all on one side), as well as different heights. I made three holes in the front, near the base, 3 in the back (also near the base) and 2 on one of the sides, near the top. I also constructed the top in such a way to provide some ventilation (later steps).
- After making the holes, your box is ready for some fine work. Take some sandpaper and sand it down so it is nice and smooth (if not already). Clean the box from dust and apply some wood primer with a brush. This will protect your wooden surfaces from moisture. Do the same to the top part, which is still not attached. To apply the primer, use a brush and follow the instructions on the can.
- When the primer dries, you can put the top on. I used two hinges placed on the inside of the box. This way, when the box closes, some space opens up on the back of the box. This is useful, as it provides more ventilation. Before screwing the hinges in, put some netting under them to cover the space that opens up.
- Glue some netting to all of your holes. Use any kind of glue that works for you (i.e. that you have lying around). I recommend using plastic netting to avoid any rust later in case you use metal.
- Your box is almost done. As a touch-up (not really required), you can add some small pieces of wood as legs, just so that it is not directly on the floor. Try filling your box with water to see if it is water proof (at least up to the level of your lowest hole). The legs don’t really need any waterproofing, so there is no need to cover them with the primer. I did not bolt the legs in, they were just attached with a bit of wood glue – in case I have to or want to replace them later. Place the box in a dry and dark place. The worms won’t get out – the box is protected and they’re scared of light. Enjoy your box! You can get a PDF of this manual here: Building a composting boxPS. This tutorial doesn’t cover how to put any bedding, worms or any maintenance yet, but I plan to add that later on, once we get a set of new worms.