This week, we’ll be detailing how you can start vermicomposting in your own home! This type of composting relies on a specific species of worms to speed up the decomposition process, and produces worm waste, or castings, which are highly nutritious when used as fertilizer for plants. Vermicomposting is very suited for the home, as waste paper along with food waste can be used. Done correctly, it produces no odours, and greatly reduces your household waste production!
How Do We Begin Vermicomposting?
Generally, we have to look at 4 components: the bin, bedding, waste material, and worms.
1. Worm Bins
The selection of worm bins is very important, as the bins are where composting occurs. Bins can range from small plastic containers, pails, and professionally made ones. You can even build your own bin!
The important thing about the bins you choose is that is must be opaque, as the worms are sensitive to light. Next, you have to ensure the bins are able to let air in, as a well ventilated bin is essential both to the survival of the worms and for efficient composting. If you use plastic bins or pails, this is usually done by drilling holes in the lids or along the perimeter of the sides. Because the lids will be on most of the time to prevent escape attempts by worms and to facilitate an appropriate environment, these holes will let air into your bin.
The bin must also not be too deep, as the specific worms used in vermicomposting do not burrow deeply. A deep bin might result in odours as the waste at the bottom is not reached by the worms. A good sized bin would be about 12-18cm deep.
Bedding serves as the habitat for composting worms. Ideal bedding is able to absorb water to provide suitably moist conditions, and its ideal state should be like a wrung-out sponge. Examples of good bedding are cardboard, newspaper (non glossy pages) and fallen leaves or dead grass. Leaves are especially favourable for worms, but because they do not absorb water well, a good mix of leaves and cardboard or newspaper is needed.
Before adding newspaper or cardboard, it needs to be shredded into thin pieces. This increases the surface area for more efficient decomposition, as these materials do not contain much nutrients for the worms. However, they do contain high amounts of carbon!
3. Waste Material
Now, on to the second most important part of vermicomposting – waste! Composting is meant to reduce waste output, and vermicomposting can do exactly that in the home! Although not all food waste can be used, enough can be composted to reduce waste volume by up to 60%. Some food waste that can be used include vegetable waste, teabags, and egg shells. Things not to use include human waste, non-biodegradable waste, and dairy and meat products. These materials, especially dairy and meat products, can attract flies and create odours.
If waste material is the second most important component of vermicomposting, then the most important part has to be the worms! Not all worms can be used for vermicomposting, however; only certain species are suitable.
Normal garden worms are ‘anecic’ – they burrow deeply and lead solitary lives. Vermicomposting worms, however, are ‘epigeic’ – they shallowly and like crowding and warm temperatures. The type of worms used in vermicomposting are known as Eisenia fetida, or red wiggler worms. They can reproduce quickly and can consume up to half their bodyweight every day! They thus make a perfect worm for vermicomposting, efficiently decomposing food waste quickly.
Getting the Bin Ready
Now that you have all the materials for your bin ready, you can start layering your bedding and food waste. Start with a thick layer of bedding, followed by food waste. Alternate the layers, but ensure that the top layer is a layer of bedding.
Add some water to the top layer until its texture is like that of a wrung out sponge. Now you’re ready to add the worms in! Place about 500g of Red Wigglers on top of the bedding, and close the lid. In about 2 weeks, you will have fully decomposed compost that you can then collect and use!
Harvesting Your Compost
Now that you have your compost ready, you need to harvest it. There are several ways to do this. You can move the compost to one side of the bin and add new food to the other side, which will make the worms migrate to the new food. The vacated compost can then be collected.
Another way is to open the lid and allow light to enter the bin. This drives the worms to burrow deeper, as they don’t like light. Once the worms have moved deeper into the bin, you can collect the worm free top layer.
The last method is to simply use a sieve to harvest the compost. A sieve will remove both the worms and their casings, leaving behind the fine compost for you.
You can also make worm tea with the castings! Just pour the castings into a porous bag and steep it in water, or put them directly in clean water. The ‘brewed’ worm tea can then be used to water plants directly, and is incredibly beneficial for plant growth.
Bins should be placed in a shaded area away from direct sunlight, and balanced on blocks above the floor. This allows the bin to be away from direct contact with heat from the ground, as the inside of the bin will reach high temperature during the composting process. The high temperatures ensure that any harmful pathogens are eliminated, as well as provide a proper temperature for the Red Wigglers, as they don’t like low temperatures.
Now that you know the basics of vermicomposting, you can establish your own composting bin in your own home! You can have fun and help save the environment by reducing your waste output at the same time – what could be better?