Wormeries have a slightly different function to a standard compost bin and therefore they look slightly different. The key difference is that a wormery is a self contained unit, often with legs, a tight fitting lid and a tap. They may be a single tank or have multiple sections. Wormeries are also known as worm bins, and vermicomposters but whatever they are called they are essentially the same thing.
A wormery is simply a container that provides an ideal habitat for compost worms to live in, a home for a colony of worms. For the worms to survive and be healthy they need food, oxygen, water and warmth which are provided as follows;
- The food comes from kitchen waste which is made up of the usual compost "greens and browns" with a few additional items which we will cover later.
- The water comes from the composting "greens" and tap water which the browns are soaked in before they are added.
- The temperature of your wormery will be driven by it's location which needs to be a sheltered spot outside out of direct sunlight and protected from frost.
- The air is all around us and trapped within the brown waste.
Wormeries come in many sizes but usually only one of two designs,
- a single unit or a multiple sectioned unit forming a tower, and are usually supplied with bedding and a small colony of worms. Compost worms like to have a separate bedding area from their feeding area however physically separating the bedding and feeding area’s isn't necessary. The bedding area of a single unit will be at the bottom and is where the worm compost is laid down, the food lies on top. Over time the bedding area will increase in size as more worm casts are produced until the wormery is full, which is when the worm compost can be harvested.
- In a sectioned bin - The leachate collection chamber will be at the bottom, the bedding will be in the next section up and the food in the top section. Again the worm compost will be laid down in the bottom bedding area which will eventually fill up. Once full, the worms will make a new bed in the bottom of the feeding area, you will be able to harvest the worm compost easily by removing the bottom section. This section is replaced at the top of the wormery and then becomes the new feeding area and so on.
When planning to buy a wormery there are a number of things to consider. The size of your wormery will be driven by the volume of waste available to feed it. Common sense tells us that a family of four will need a larger wormery than a single person living alone, however if the family of four are also managing a cold compost bin they may only need a small wormery, therefore think about
- how much waste you have available to feed your worms, factoring in the waste that you cannot put in a cold or hot compost pile which you can feed to your worms.
- Having invested in a small wormery it can be expensive to upsize, if you think you need a small unit now but might need to upsize in future think about selecting a style which comes in sections where additional sections can be purchased.
A natural by-product of making worm compost is a liquid waste or leachate called worm tea. Worm tea must be siphoned off regularly or your worm colony will drown. The tea is very concentrated, it can be stored then diluted and used as a liquid fertiliser or poured away. Production of worm tea is one of the main reasons seasoned composters keep a wormery and a compost pile, the leachate in a compost pile is difficult to collect. Concentrated worm tea needs to be stored away from access by children and animals in sealed containers.
Your worm compost will be ready to use straight away, however if you want to store it allow any worms in it to escape before you bag the compost up.
A worm colony will multiply to fill the space available to it and no more. Therefore it is beneficial to reduce the colony size occasionally to keep a healthy colony. If you are managing a cold compost bin the worms can be transferred there and will live quite happily. If you do not have a compost bin then release the worms in a sheltered leafy place where they can sink quickly into the ground.
If you have any additional questions about wormeries please ask me and I will do my best to help.