How to Start Vermicomposting

Back when I lived in Seattle, a friend mentioned one day how easy the worm bins he used were to make. I looked at him blankly…er – did you say WORM bins?

He backed up a step and explained that he used worms to compost for him – also known as vermicomposting. He also told me how easy they were to keep and regaled me with tales of worm tea and worm castings (aka poop!)

He offered to bring me one of his bins and set me up with worms. I gladly accepted. And you know what? He was totally right! Worms are awesome!

There are many different ways to house your worms and harvest the tea and castings. Here’s how we practice vermiculture at our house.

How to Start Vermicomposting

Worms 101

Worms can be used to compost just about any fruit or vegetable waste – cores, rinds, shavings, peels, and ends. They require moistened bedding material (shredded paper works great) and some grit to help their little innards (a bit of dirt and/or crushed eggshells). Vermicomposting works best when the temperature is between 55 – 80 degrees F.

The temperature range can be a bit tricky for some climates (mine being one of them). For those in warmer climes – keep your worms indoors for the summer months (a utility room, pantry, or laundry room work great!) For those in cooler climes – keep your worms indoors (or by the water heater in the garage) during the coldest winter months. Basements (if you’ve got one) are a popular location for worm bins.

Worms love all your fruit and vegetable kitchen scraps. Some people cut their scraps into small pieces, some don’t. My theory is the simpler the better so I don’t.

No meat, dairy, oil, or bones should find their way into your bin.

Vermicomposting on a small scale like this can’t handle the slow decomposition of animal waste (in other words – it’ll smell bad!)

I tend to avoid citrus also because the jury seems to be out on whether or not this will harm your worms. Other add-ins that are popular with the worm crowd are teabags, coffee grounds with or without filters and eggshells.

How many worms do I need? For most vermicomposting households, starting with about a pound of worms is right. Worms can eat more than their own body weight per day. Most places that sell worms (via the internet or other local sources) sell them by the pound.

Remember, that one pound of worms will grow to be more – worms are good at reproducing. At that point, you can up the amount of waste you put into the bin or thin out the worm herd and gift a neighbor or friend with their own vermicomposting system (aka worm bin.)

The Simplest Worm Bin Ever

To start with I purchased two 10 gallon plastic storage containers. You’ll only need one lid for the both of them. I picked mine up on sale for $5 each.

Step One

On one of the containers, you will drill smallish holes (a bit smaller than the diameter of a dime) all the way around the top (approximately an inch or three apart). These holes will help with ventilation of your worms and their food (i.e. your food waste). Lack of air can mean a very stinky bin.

Step Two

Next up is drilling holes throughout the bottom of the same container. This will help with drainage of that wonderful worm tea (into the other plastic storage container) and with ventilation. We sprinkled the holes throughout in a symmetrical pattern.

Step Three

You’ll need some screen to cover the bottom of the top container. This will help (but not entirely prevent) your worms from crawling through the bottom holes into the lower container. I just eyeball it and cut some basic window screen to size (picked up at my local hardware store).

You’ll end up with too much if you buy a whole roll, but that’s okay because you can use it to make worm bins for all your friends (which is what I intend to do).

Step Four

Either take the contents of your shredder or grab some paper to shred. You’ll need enough to cover the bottom of the container about 5 or 6 inches deep (about 3/4 full). I usually avoid the glossy magazine stuff, and instead aim for basic white paper and/or brown grocery bags (my favorite!)

Wet the paper a bit until it’s about as damp as a wrung-out sponge. You can dunk the paper in water and squeeze the excess out or take a spray bottle and mist away until you’ve hit the right moistness. The paper shouldn’t be all balled up, but should be fluffed up a bit. This helps the worms find their way through it.

Step Five

Nestle the two plastic containers together and put the lid on the top one. That’s it! Your worm bin is assembled. Now you need worms!

Step Six – Optional

For ease of draining the worm tea off – you can opt to drill another small hole in the side of the other container (the one without the ventilation holes) and plug it with a small rubber stopper.

Getting Started

So your worms have showed up and your bedding and bin are ready to go. This next part is really complicated…put your worms in your bin and leave them alone for a while (to let them adjust to their new home). Give it a day or two. Tough huh?

After that you can start feeding them. My girls are pretty excited about the worms so we have been feeding ours little bits daily. But you can save your scraps and feed them a few times a week if that works for your schedule. Best strategy here is to scatter the food scraps UNDER the bedding material. This helps to keep smell and fruit fly issues at bay.

Other Tidbits

Make sure to check the moisture level in your worm bin frequently – it should be wrung-out sponge moist at all times. Too dry can hurt your worms. Too wet can lead to smell issues. A squirt bottle is your friend here – a few squirts every so often is all it takes to keep them damp.

You’ll need to add more bedding material occasionally (as the old stuff disappears). Also be sure and drain the worm tea off every so often. I save old spaghetti jars to use to store the worm tea in.

Be sure and get your kids involved in your worm bin project. Mine are absolutely thrilled with ours!

And remember – Happy Vermicomposting!!