Good evening! This past weekend I finally harvested the product of a vermicompost that I started a few months ago and was able to get 3.5 lbs. worth of worm casings! This was very exciting for us since this is one experiment I was a little unsure about, especially doing it all indoors. I am happy to report that this is one experiment we will definitely keep going.

What is Vermicomposting? Essentially it is the act of using worms and microorganisms to turn kitchen scraps into a very nutrient dense soil. A type of composting, vermicomposting is capable of being done in a small area and, as we’ve just discovered, all indoors! I had heard a lot about worm bins and composting and wanted to try it because I felt bad we had kitchen and plant scraps going to waste and were unable to have our own outdoor compost bin. A worm bin was really easy to make and even easier to upkeep, the steps are below.

Creating a bin:

Find a container. For ours we used two 12-gallon storage containers from the hardware store. Why two? One is the actual bin itself and the other is for nesting it in so whatever falls out of the air holes is collected. Drill air holes into the container. We drilled a few in the bottom and around the sides towards the bottom and another set towards the top (see picture), we also drilled some in the lid. Holes were 1/4″ in diameter. You want enough to allow for airflow but not too many that worms start escaping or falling through. We collected shredded paper, cardboard, and kitchen scraps for bedding. As far as kitchen scraps go you want to be careful not to add too much or it will start to rot faster than the worms can eat it. This will create an unhealthy environment for them as well as for you! You want to stick to just vegetable/fruit scraps, no meat or dairy scraps. You can add ground coffee, used tealeaves, and finely ground eggshells as well. We mainly stick to leafy vegetables, potato peelings, tealeaves, and plant matter from my garden. We found cornhusks are hard to digest fast and tend to grow a lot of mold. Once you have bedding in place you need to moisten it. One method is to soak the bedding in water for 24 hours, wring it out, and then place it in the bin. You can also sprinkle it with water; just make sure the bedding is moist but not drowning. Please note that the containers we used are very tall but we did not fill the bin up all the way. Worms only live in about a 6″ layer so if you do a lot more than that then the material will not get digested, it will only rot and start to stink. Add worms! Worms used for vermicomposting are red wigglers. While you find other beneficial worms in your outdoor garden, for vermicomposts generally only red wigglers are used. I ordered mine from Amazon and they arrived safe and sound in their own little bag. (1000 live count) Once the worms are added, the bins were nested (make sure there is room for airflow) and the lid gently placed on top (not clamped down). For the first few days we did have some escapees so I kept it in a spare bathtub until the bin was established. Once the bin was established it went into the closet and was basically forgotten about. About once a month or every other month we would add more scraps or bedding and make sure things were still moist, but that was all the upkeep that was needed.

… wait 4+ months…

Harvesting!

Now I will admit since this was a homemade compost bin I was a little unsure about how to actually harvest the worm casings from the bin. There are quite a few pre-made bins you can buy out there that have harvest methods built in, but for the homemade types you must do it by hand. There were several ways that I read about online, but what I finally ended up doing was dumping the whole bin out on to a tarp. I then used a slotted bowl from a salad spinner (really the only thing I had handy, use whatever works for you) to sift through and separate the worms and bedding from the actual soil. I put the bedding and worms back in the bin with some fresh matter and that was it. It was easier than I had imagined it to be! I started the bin in August and harvested in March, so 8 months, with 1000 worms, produced 3.5 lbs. of soil. Not too shabby for something I started in August and then forgot about. The soil was then spread on my plants and citrus trees, which I expect are going to enjoy it very much. Try it yourself!

More information on Vermicomposting can be found here or here, and in the book Worms Eat My Garbage.