There are various types of vermicompost systems available for the home use. This is a basic overview of each system type.
There are two main types of systems are simple bin and continuous flow through
The most common and cheapest system is a standard storage bin or tote. These can be found at any big box store and any home improvement store. Totes come in a variety of sizes and can offer flexibility for those with limited space. Some common totes are Rubbermaid Roughneck, Home Depot HDX, and Sterlite. The most important requirement is that the tote cannot be see-through/transparent. Worms DO NOT like light.
- Retains moisture very well
- Can help prevent pests such as fruit flies (with lid on!)
- Can be left alone for very long periods (set it & forget it)
- Can be used as a single batch with the intent to harvest the vermicast only once
- Less airflow compared to continuous flow through systems
- Holds onto moisture too well at times which can lead to anaerobic conditions
- Overheating can be an issue if too much nitrogen (food waste) is added
- Material at the bottom can become compacted and sludgy
- Harvesting vermicast can take longer as it typically needs a drying out period
The totes do require some preparation before starting the system. One would need to drill holes on the sides and/or lid for airflow, which requires a drill and drill bits. There are also some different ideas out there on the best way to set these up. Some recommendations include using two totes that are stacked in one another and others where only one tote is required. There are pros and cons of each but my preferred is to use a single tote as it is more cost effective and is easier to stack bins for multiple systems.
Continuous Flow Through
The other common system for home use is the continuous flow through system. These are systems that have a fairly large opening at the bottom that allows for easier harvesting of the vermicast. These are typically made from a cloth or poly material that is not rigid. Similar to the bin systems there are a variety of sizes but the sizing is much more limited. Some of the brands include the Urban Worm Bag (UWB), VermiBag, and the Worm Inn (no longer available).
- Excellent airflow which prevents anaerobic conditions
- Food scraps tend to break down more quickly
- Easy to harvest vermicast
- More forgiving if overfeeding
- Better airflow can lead to drying out
- These tend to take up more room than the plastic bin systems
- Requires more maintenance by adding moisture and more consistent harvesting
- More expensive startup cost – some require building a separate stand
These systems also require some set up and some pre-planning in determining where to place them. The UWB can be purchased with a stand and is very easy to set up. The VermiBag requires the user to build his/her own stand but can provide greater flexibility such as including adding casters, built in harvest trays below bag, and having multiple systems on a single stand.
I also left out other types of continuous flow through systems such as the Vermibin and stacked plastic totes. These types require much more set up time and one to be handy…which I am definitely not! Not that these systems are bad! I just think of them as a hybrid between the two.
Which system is better?
As with all things vermicompost…it depends. I know that is quite unhelpful…but it really depends on one’s needs and goals. Also, one may have to trade-off certain benefits of one system due to constraints. Here are some factors that would direct my approach:
- Limited space
- Cost of system
- Time for maintenance – minimal check ins and only harvest vermicast one time
- If one travels frequently or is away from the system
- Produce fewer food scraps – only produce scraps for one or two people
- All types of composting worms are compatible – it isn’t limited to just Red Worms
Continuous Flow Through
- More forgiving for beginners
- Better airflow can reduce the chance the system overheats or stinks due to overfeeding
- The system dries more quickly which can be beneficial if one adds too much water rich food scraps or over waters the bedding material
- Need for vermicast quicker and more frequently
- Generally produce a lot of food scraps – family of four, etc
This is not a fully comprehensive list! It just provides some thoughts on where to begin.