Vermicomposting is the process of using red worms to break down organic matter into a usable fertilizer. Vermicomposting is an excellent way to dispose of food scraps from within the comforts of your own home. This composting method is great for apartments, or locations that do not have enough space for a traditional compost pile.
While any Earth Worm will feed on food scraps, vermicomposting requires the use of worms that are best suited for the environment. Red Wigglers (Eisenia fetida) and Red Worms (Lumbricus rubellus) are the two best types of worms to use for vermicomposting because they live within the top 12 inches of soil (perfect for composting), they are able to live in highly populated areas, and they will typically swarm to their food.
To purchase Red Wigglers or Red Worms, the easiest way is to contact your local bait shop to see if they carry either species, or you can order them online. If you order them online, the cost of each species will vary, but you can expect to find them for approximately $25 per pound (plus shipping).
The easiest way to determine how many worms you will need for composting is to weigh up the amount of food scraps you produce in a given week, and divide by seven to calculate your daily average. In one day, worms will eat half of their body weight in food; so if you generate half a pound of food scraps per day, you can use one pound of worms in your compost bin. For most small households, one pound of worms will typically be enough to start.
How Much Food to Give the Worms
When you first start your compost bin, give your worms time to adjust to their new surrounds by reducing the amount of food scraps you give them. Worms can take up to two weeks to fully adjust to their new surrounds. Start out by giving your worms a small amount of food; when they eventually start to consume the food, slowly increasing the amount until you have reached your normal quantities.
Constructing Your Bin
The first thing you will need to begin your vermicomposting operation is a bin. Vermicomposting bins are unique from other composting bins in that they are shallow, and should not exceed 1.5 feet in height.
The dimensions of your bin will also depend upon the amount of food waste your household generates in a week. Your compost bin should be 1 square foot for every pound of food waste you generate in a week. For example, if your household generates 3 pounds of food waste each week, your compost bin should be at least 3 square feet in size.
Your vermicomposting bin should also have plenty of ventilation for your worms. If you are constructing your own bin, 1/4 inch holes should be drilled around the perimeter of the container to allow for adequate air flow. Holes may also be drilled into the bottom of the container to allow for excess water or leachate to drain out of the container, which will also improve the overall quality inside of your compost bin (do not forget to place a drip pan underneath your bin if you are using this method indoors).
If you would rather buy a vermicomposting bin than make one, there is a wide array of them available online. Simply search "vermicomposting bin" and you will be able to find home composting bins ranging from a few dollars, up to several hundred dollars.
Once your bin is constructed and you have purchased worms, you will need to find bedding material for your worms. There is a wide variety of materials that can be used for bedding in your bin, so you will have to decide which material is best suited for your situation.
Some of the best materials to use for bedding are cardboard and paper. Cardboard boxes and egg containers are perfect materials for bedding in your compost bin. Simply shred the materials, as seen in the image, and spray with water as you add it to your bin.
Products to Avoid
When adding paper products, avoid materials that are glossy, bleached, or heavily colored. These materials could potentially be toxic to your worms, so it is best to avoid them in general. Most items such as newspapers, paper documents, and mail documents are perfect to use as bedding.
By shredding these materials, you are allowing for increased air flow in your compost bin, and making it easier for your worms and other microbes to break down the material. Other items that may be used for bedding include: coconut fiber, leaves, straw, hay, and wood chips.
Harvesting Your Compost
Depending on the size of your operation, you compost will be ready anywhere from 2 to 6 months. You will be able to tell that you compost is ready when the contents of your bin are dark brown, small, and no longer recognizable. Because this method uses worms to create compost, it can sometimes be difficult to harvest the finished product. There are several different methods you can use to safely remove the compost, while causing little harm to your worms.
The migration method may be one of the slowest methods for harvesting compost, but it does not require a lot of work on your end. To start, move all of the compost to one side of your bin, and place new bedding in the open space. When you go to add food to the compost bin, place the items in the area with new bedding, and avoid placing any new food items in the area you wish to harvest. Over time, the worms in your bin will travel to the area with new bedding in search of food. In 1 to 4 weeks, the worms in your bin will have moved to the new side of your compost bin and you will be able to harvest your compost
The cone method is faster than the migration method, but it involves a lot of hands-on work, and you should be prepared to get dirty. The cone method works by utilizing your worm's sensitivity to light to harvest the compost. To use this method, you will need a tarp, or something you are not afraid to get dirty, and a light source. Harvesting outside in a sunny location is ideal; but if you have to harvest inside, bright lights will be required for the entire process.
First, spread your tarp out and dump the contents of your compost bin onto the tarp. Next, you will need to form multiple cone shaped piles of material on the tarp. After a couple of minutes, you may begin to harvest the outside material of the cones until you begin to encounter worms. When the worms are exposed, they will dig deeper into the pile to avoid the sun, at which point, you will be able to repeat the process of removing compost from the piles until you are primarily left with worms at the bottom of the pile.
If you are going to use this process, it allows for some multitasking while you wait for the worms to progress further down the pile, but you cannot wait too long as you worms will easily die if left in the sun for an extended period of time.
Vermicomposting does not require as much maintenance as hot composting, but to successfully vermicompost, a few easy steps are required to keep your worms happy and healthy:
- Avoid exposing your worms to direct light (unless harvesting compost). Exposure to light will dry out your worms, and can potentially kill them if exposed for extended periods of time.
- Worms require three primary things to keep them happy and healthy: food, moisture, and darkness. If you maintain the correct balance of each, your worms with thrive.
- Worms do not have teeth; because of this, they will require sand, other small rock fragments, or egg shells to help them with digestion. To keep your worms healthy, sprinkle some of these materials on top of your compost once a month, or when you add bedding, to aid in your worms' digestion.
- For your worms to survive, your compost bin should be placed in an area where the temperature falls between 55 to 80 degrees Fahrenheit. Many people will often place their bins under their kitchen sink or in their basement to maintain the correct environment. Your bin may also be placed outside, but additional insulation or shade will be required to stay within the ideal temperature zone.
- One common problem that can be experienced during vermicomposting is the presence of pests such as fruit flies. One way to avoid attracting pests is to freeze your composting material before you add it to the compost bin. This process will not only kill off any fruit fly eggs, but it will also aid in the break down of your food scraps.
- You should avoid using onions, broccoli, ginger, garlic, and potato skins in your vermicomposting bin as they will take a long time to break down, and the can create odors. Other items to avoid include: bread, citrus fruits, meat, dairy products, candy, and heavily oiled products (potato chips).