Make your own worm bin | WWF South Africa

Make your own worm bin

Make your own (earth) worm bin.
Earthworms produce excellent compost, rich in nutrients, an great solution for small gardens.
  1. A heavy plastic bin with a lid makes an ideal worm bin, but you can use just about any container (wood, metal or plastic). Try to avoid placing your worm bin in direct sun.
  2. Drill holes underneath and on the side at the bottom of your worm bin to allow for drainage. Stand the container on bricks to improve drainage and to allow air to circulate. Earthworms need moisture at all times, but they will die if their surroundings become soggy and air is in short supply.
  3. Place enough sand or gravel at the bottom of the bin to come up a few centimetres above the drainage holes to help drain excess moisture.
  4. Place some sort of base, either cardboard or wood, above the gravel or sand to provide a foundation. Leave a little space between the board and the container to allow water to drain.
  5. Place a layer of shade cloth above the base to prevent the worms from escaping.
  6. Next, put some bedding material - mature compost mixed with shredded newspaper -  in your bin.
  7. Put 50 - 100 earthworms in your bin and feed them chopped up kitchen waste. Leave them undisturbed for a week. Earthworms occur naturally in most gardens and they can be found in moist soil near rivers. Your local nursery should be able to help you source worms.
  8. You can add a final layer of shredded newspaper each time you put something in the bin to keep fruit flies away. If you are not using a bin with a lid, cover your container with hessian to keep birds from eating the worms and to keep the bin moist and dark.Once a week, turn the top half of the worm bin with a fork aeration. You could also work in some crushed egg shells to help neutralize acid which is bad for the worms.
What to put in your worm bin
  • Start gradually, adding small amounts to the bin.
  • Worms like to feed on small amounts of food often so peelings and other vegetable scraps from the kitchen are ideal. By about the fourth week,the worms should be able to deal with the amount of waste produced by most households. Tea bags and coffee grounds are also acceptable.
What to keep out
  • Peel from citrus fruits like oranges and lemons and potato peels will make soil too acid for the worms.
  • Meat will attract flies.
  • Too many grass mowings will heat the bin up which may harm the worms.
  • The earthworms will eat some weeds, but avoid tougher, perennial weeds.
  • Don’t put in cooked food.
How to harvest compost
The contents of your worm bin will be ready for harvesting in about three months.
  1. A week before harvesting, add some vegetable matter to bring most of the worms to the top.
  2. Remove the top half of the contents and place to one side.
  3. The rest of the contents of the bin can be used to feed your garden.
  4. Restart the cycle by placing some compost on the shade cloth and then adding the top half (containing the worms) that you removed first.
(Courtesy Barbara Jenman)

If you live in Cape Town you can purchase a worm bin made from a used tyre from: