How to Start a Worm Compost Bin
Ready to talk worms? While I was taking my master gardener classes, I quickly learned during a compost seminar that I was the only person in my class composting with worms. I felt like such a huge dork because I was really into it. I am so fascinated by composting! While vermicomposting, or composting with earthworms, sounds just like what you would do outside with your regular compost pile, it's actually a little different!. For the past several months, I have been working with the company VermiTek, which supplied me with their awesome worm bin called the VermiHut. I love it! It's easy to put together, easy to use, and it stays really clean, which is always nice.
Vermicomposting is generally used for composting kitchen waste. If you have read my composting basics blog post, you'll know that mainly consists of vegetable scraps, paper towels (clean of any chemical cleaners), coffee grounds, and eggshells. Worms can also eat shredded newspaper or paper that isn't heavily colored or glossy, hair, grains, cardboard, garden leaves and clippings, and wood sawdust. While you can keep worms in much larger structures, for at home composting you'll find bins similar in size to the one I have. It's pretty small, can be stacked for height as your worms and compost contents grow, and fits easily in your kitchen. We keep ours in the new greenhouse (which will have windows installed sometime this summer! Worms need to be kept at a comfortable temperature to thrive, around 50-70 degrees. Some people keep their bins in the garage, but if you live in a place where temperatures get to freezing, you may want to rethink your spot if your garage isn't heated.
Why keep a worm bin? Mostly for one reason: they create worm castings. Worm castings are a highly active and beneficial mixture of bacteria, enzymes, organic plant matter and animal manure, and earthworm cocoons. They are rich in nutrients and contain over 50% more humus than topsoil or compost. What is humus? It's not the yummy bean dip - you're off by one letter! Humus is a component of soil, the part made up of decaying plant matter which is SO good for your plants. These are things like phosphorus, magnesium, potassium, calcium, and nitrogen. And while you can get these things from fertilizers and animal manure, they have to be diluted and broken down before using them directly on your plants. With worm castings, you can just add them immediately to your plants, directly touching the roots, and they won't burn! For my entire garden last year I did not use a single fertilizer; I only used worm castings! They are not technically a fertilizer; they're a soil amendment, and they work like magic. You can use this worm product for potting soils, to fill in garden transplants, as mulch, and even made into a tea when diluted with water that you can spray on your plants. Plus you're growing a colony of earthworms! The VermiHut can house up to 10 pounds of worms, and they can be added to your soil, which is always a good thing.
Worms prefer a comfortable living environment just like all living things. The choice of bedding you use can greatly affect the health of your worms, so be careful in picking out what you might use. If you choose to try out the VermiHut, you are provided with a brick of coconut coir. This stuff is really cool. It's dehydrated coconut husks, compacted into bricks, and is used for water retention. You can use it to make your own potting soil! It's being chosen more and more as peat becomes difficult to harvest in many places (did you know we've lost most of the peat available to use a natural resource?) and coconut coir is the waste product of most of the coconut products we love so much now, like coconut oil and milk. Nothing goes to waste! I used this for my worm bedding material along with a mix of my own compost, dried grasses and leaves, and shredded newspaper.
Setting Up Your Worm Bin
- Find a bucket that is over 1 gallon. Fill it with 1 gallon of water and soak your coconut coir brick. Let it sit for a few minutes until it begins to break down; you can speed up this process by helping it break apart with your fingers.
- Once broken down, begin to pull out handfuls of the coconut coir, squeezing out the excess water. You want your worm bedding to be moist, but not wet. It should feel like a damp sponge or washcloth. Test the wetness by squeezing your material; if only one or two drops of water drips out, then it's perfect!
- Begin filling up the first level of your worm bin. The VermiHut comes with up to 5 working trays. You begin with one and as time passes and your worm colony grows, you add the other trays. Place your first tray on the base and spread a few sheets of dry newspaper on the bottom. Fill with the coconut coir. Mix in several handfuls of compost, soil (not commercial potting soil or pure clay), and shredded newspaper. You may also added in some crushed eggshells, dried leaves, or dried grasses for a good carbon mix! With your hands, mix everything well. The tray should be about 2/3 full.
- Now you're ready to add your worms! I always mail order my worm from Uncle Jim's, but if you have a local farm that sells earthworms (make sure they are the red wigglers) you can always go there to pick them up. I started with 1,000 worms. When they arrive, they are going to look a little small and deflated. This is totally normal; they get stressed out while traveling! They may even try to escape from your bin and fall out onto the floor. Don't worry; just pick them up and place them back inside. To get your worms adjusted to their new home, adding them to the bin is really easy...
Introducing Your Worms to the Bin
- Place the worms on the surface of the bedding and cover them with a dampened sheet of newspaper. They do not like sunlight and prefer the darkness of soil, so they will quickly dig their way into the bedding.
- Just like in your garden, worms live in colonies. Red Wigglers are preferred for gardening as opposed to Night Crawlers because Night Crawlers will aerate your soil and then leave! Red Wigglers live in the same place for decades, so they make great worms for a bin. Make sure to not spread your worms out. Don't place some in each corner or try to dig them underneath the soil. If you mail order worms, they'll arrive in a big clump that looks like an alien. Just leave them like that and cover with the newspaper. If you are planning to put your worms out in the garden once the colony grows, you'll do the same thing, just out in the open. Don't spread them everywhere! Leave them in their little family group, and they will do the rest.
- If you are having an issue with worm escapees, try putting a lamp next to the bin for a few days. They are encouraged to burrow and stay in the soil.
- Once covered, water with about a 1/2 cup of room temperature water and close the bin.
Feeding Your Worms
When can you feed them? This part is a little bit frustrating! You are promised beautiful compost within 2 weeks from some companies, and although the processing is a lot faster, that's not necessarily true. You can't just add your pile of kitchen scraps to the bin on day one. If anything, add a handful of crushed eggshells to the mix and then leave them for a few days. A common mistake for beginners is overfeeding the worms. Your scraps don't just disappear overnight! They still go through a decaying process much like in a compost bin outdoors.
To begin feeding your worms, after letting them adjust to their new habitat for a few days, place little bits of food scraps at each corner of your bin. You can even bury them a little. For more efficient composting, cut the scraps up into smaller pieces so they break down more easily. Once you see the food has been consumed and most of it is gone, you may start adding more. You may have notice the banana peel on my table in the photos! I ripped that up into little bits for this set of worms.
After about 3-4 weeks, when you notice that half of their food is gone, you'll know it's time to feed again! If there are a lot of scraps decomposing, then your bin might start to smell as well as begin lowering the pH of the habitat, which is deadly to your worms. Just go slow, and it will happen for you! This is part of the reason why some people don't enjoy having a worm bin solely to compost their waste; you can only use so much at a time! I highly suggest only getting a worm bin if you also have a regular compost pile or if you are just wanting to harvest more worms and castings.
Once everyone is settled, all there is left to do is wait! It's good to place the bin somewhere that you are reminded to check in on it at least once a week. When we lived on the Little Homestead, I had the bin in our mud room and actually forgot about it quite often. Because you cannot place your kitchen waste and other compostable materials into the bin for a while, it's easy to not place anything in it at all. I highly suggest putting a reminder on your calendar or phone to check the bin every week to make sure things are moving, castings are being produced, and all of the worms are still alive. Getting all of these supplies is not necessarily cheap, but is is a lot cheaper than buying a bag of organic worm castings all growing season. Trust me - those add up!!! Growing and harvesting your own worm castings is an excellent way to save some money and control the contents of those castings, if they are organic or not.
Thanks for reading! Have a question that I didn't cover? Leave a comment!