How-to: Vermicompost!

By: Laura Binford

Want to improve your soil health, process your own food waste and have the cheapest pets imaginable? Allow me introduce you to vermicomposting. Vermicomposting is the process of using worms to break down food scraps and other organic matter into a valuable soil amendment called vermicompost, or worm compost. It is one of the best ways to take care of food waste and provide nutrients for your garden.

The Basics

You’re going to need worms, but you don’t want just any worms. Some worms are invasive and can actually do more harm than good when released into the garden. You want earthworms, specifically red wigglers. These can be purchased at any bait shop, but if you’d like to know where your stock comes from, there are many reputable worm farmers (yes, that is a real thing!) who will happily ship them to you. Your new pets will need food, but don’t go emptying the whole fridge into the worm bin just yet! There are a few things you’ll want to avoid. All vegetable scraps are encouraged. Never put meat, dairy, or eggs into your worm bin, and avoid things that take a very long time to break down, like avocado pits or citrus.

You will also need to provide bedding material. Without this, the food scraps become a smelly, rotten mess and your worms can become sick. Shredded newspaper is the most accessible, but plain, brown cardboard works as well. You just want to avoid any glossy paper or cardboard. If you notice your worms are staying too moist, simply add more of these “browns”. If you see that your worms are sluggish and dry, mist them with water and add more food scraps.

The Setup

Vermicomposting doesn’t take much time, energy, or space; my first worm bin setup was housed in the laundry closet of my 600 sq. ft. apartment. There are several different methods to vermicomposting. When you are setting up your bin, consider the space you have, how much money you’d like to invest, and time you want to spend harvesting your castings. The single bin setup is the simplest and cheapest to set up. These bins can be made of two plastic storage containers and one top. Drill holes around the bottom perimeter of the bin for drainage and an additional row around the top for air flow - remember, these are living creatures! Place the bin inside of the un-drilled storage bin; this will be used to trap the “juice” released when the worms are busy working. You can use this valuable, nutrient-dense “worm tea” as fertilizer, just make sure to dilute first! Just like in their natural habitat, your worms want to live in the dark, so make sure to attach the top lid tightly.

After a couple years fumbling with the single bin setup, I’ve upgraded to a worm tower. There are many models available for purchase, both plastic and wood, but can be easily built with hardware cloth and wood. In this system, there are stackable, mesh levels. The worms, food, and bedding are placed in the lowest level. When the worms have almost fully processed the food in the bottom, you begin to add food and bedding to the next level. Your brilliant new pets get the message and move up to the next level. The process is repeated until the top level, and then begins again from the bottom. I love this method because the castings are easy to harvest, simply remove the bottom tray and use the compost as needed. No sifting necessary!

The Benefits

When your worms have processed your organic materials, you put that hard work to use in your garden! Do not expect your worm compost to be as fluffy and uniform as the worm castings you buy in garden centers. When it is “done” it should look like rich, dark compost with few to no whole pieces of food left. If you are using the single bin method, you will have to sift out the finished castings from the organic materials and the worms. You can do this with your hands or a homemade sifter made from hardware cloth on a wood frame. Don’t worry if you miss a few worms! Red wigglers reproduce at a rapid and almost constant rate, and your bin won’t even miss them. When you notice your bin is becoming too crowded, you will want to set some loose.

Find a spot in your garden and release them into the soil to do their thing outside. Cover them with leaves so they will feel welcome in their new home. You could even give the extras to a friend! Maybe it’s just me, but I’d love to receive worms from a neighbor. Enough cookies! Bring the worms!

I use my worm castings on almost everything in the garden, including flowers, shrubs, trees, and vegetables. MiracleGro has nothing on these worms! Chemical fertilizers are not only harmful to our natural ecosystems, but they are also harsh on our plants and our soil. Worm castings are a much gentler fertilizer that is kinder to our plants, waterways, and our wallets! Aside from the initial investment, this is an essentially free way to have fertilizer (and a few hundred wiggly friends) for life.