Worm Composting in Edmonton

Earth’s General Store no longer offers worms for composting. This page and the information contained on it are for reference to help people explore and become a success with Worm Composting in Edmonton. I have listed a few local suppliers of worms in the Edmonton area at the end of this blog post.

Earth’s General Store has been offering worms and worm kits for worm composting in Edmonton since we opened the store in 1991. Composting is one of the top 10 things people in our society can do to help the world. It allows us to take our organic food waste and turn it into a very beneficial end product.

Worm composting (vermicomposting) is a process that people that live in smaller spaces and don’t have access to an outdoor composting system can use to recycle their organic ‘waste’ materials into a fantastic end product – worm castings.

Worm composting is quite different than outdoor composting. With worm composting we are using macro-organisms to eat the food and poop out the rich material (think of it as worm manure 🙂 ). Worms don’t have teeth to chew on food so micro-organisms, bacteria, and fungi have to work on the organic matter to break it down into particles that the worms can ingest.

Sorry – We no longer carry worms since we have not found a suitable supplier (our supplier of over 20 years died in the fall of 2015). We suggest that you check out Kijijii Edmonton and I am told there are several people selling worms there. Sorry for any inconvenience this may cause anyone.

This page is provided as a resource for worm composting only.

What will you need?

Worms – people use a species of worm called the red wiggler (eisenia fetida) as the composting worm of choice. Red Wigglers like high organic environments (compost piles, manure piles, etc.), they do well in close quarters with other worms, they like a temperature of 15C – 25C (so your home at 18C-21C is perfect), they are small but eat half their own body weight per day, and are industrious and quiet guests.

Bin – we recommend using a 53L Rubbermaid Roughtote(R) for a bin. This size provides adequate surface area and good depth. We drill 9 holes that are 1″ in diameter in the lid. We like these bins because they are readily available, fairly inexpensive, durable, and if you decide not to have a worm bin 5-6 years into the future you can just wash it out and use it for some other purpose. It is important that the bin gets adequate air.

Worm bin with holes drilled out.
Worm bin with holes drilled out.

Organic matter – food ‘waste’. Basically, anything that grew out of the ground that is non-toxic. This includes but is not limited to; pasta, bread, fruit, vegetables, etc. The only exception is that many people add crushed egg shells. Don’t put meat, fish, cheese, milk or eggs into the bin. It isn’t that the bin won’t be able to ‘digest’ these items it is just that they are hard to break down, will be around for a long time and will likely putrefy (making the bin less pleasant) and likely attract maggots and such.

Bedding – Many sites suggest shredded newspaper or some other form of cellulose. We recommend a light soil medium. We use a product called Pots & Plants which is a potting plant mixture. It is light, has a variety of materials in it, organically made in Alberta, and is reasonably priced.

  • Some of the reasons why I like soil over paper/cellulose:
    • Soil is closer to the worms natural environment
    • Soil handles moisture well – moisture is readily transmitted throughout the bedding mixture (worms breath through their skin so the bedding needs to be damp for them to be healthy)
    • It provides a dark environment – worms don’t like light
    • It is natural – worms will eat the bedding when there isn’t better food about.
    • It allows air to penetrate throughout it

Trowel – or some other tool to excavate the deposit site and moving the bedding about.

Marker – you will be depositing your organic material into the bin. Worms don’t like to be disturbed and the bacteria and fungi like dark and damp spaces so when they are exposed to light and air their environment is disrupted and sets back the rate of decomposing. What we recommend is that you deposit in an organised manner.

Water – since worms breath through their skin we need to make sure that the bedding is damp (not soaking). When we assemble the bin we will be adding water to the bedding to ensure it is damp enough. We recommend adding 4 Litres of water, to begin with and more if needed. City water has chlorine in it which is not overly healthy for living organisms. If you take about 8 Litres of water and let stand overnight most of the chlorine will evaporate out of it and the temperature will be approximately that of the indoor ambient temperature. The worms will appreciate this care you have taken. If we just took the cold tap water and then threw the worms into the bin the worms will go through a bit

Information – we usually provide a short information session to people picking up worms. The City of Edmonton also produces a guide on Vermicomposting. These guides are included in the kits we make up for sale or available free at the store. There is LOTS of information on the internet about worm composting as well.

How to put it all together?

  • Take your bin with holes in the lid and add enough bedding to be about 1 inch over the side ridge in your bin (about 3 inches below the lip of the container).
    • Just like you and me, worms need air to live. The lid should have adequate holes drilled into it but it is also important that the surface of the bedding is not too far away from the lid. If the surface is too far away from the source of fresh air the air inside the bin can become stagnant and not the healthiest. We want to keep our bins aerobic.
  • Pour 4 litres of water over the top of the bedding.
  • Stir.
  • Let it sit for about 30 minutes.
  • Check to see that all areas of the bin are moist – like a wrung out facecloth. If not add more water.
  • Let the bin sit for about 2 hours or overnight. This allows the moist bedding to get up to room temperature and some of the chlorine to evaporate out of the water.
  • Dump the bag/container of worms onto the surface and spread across the surface. The worms will burrow into the bedding
  • Let the worms distribute themselves throughout the bin (a couple of hours should suffice).

How to operate the worm bin – feeding the worms

Now that you have assembled the bin, put the worms in, and have some organic material to feed the worms we can actually start.

  • Remove the lid
  • Visually divide the surface of the bin into 6 areas. What we do when we are showing people this is that we will take the trowel and draw lines on the surface of the bedding – one along the midway along the length of the bin and two lines along the width (1/3 of the distance apart). These areas will be your deposit site/holes.
  • With your trowel dig a hole in the top left corner of the bin. The hole should be about 1/2″ away from the sides and deep enough that it will accommodate your deposit or organic material. You should not dig all the way to the bottom of the bin but leave about 1 inch of soil at the bottom of your hole.
    • We always start on the top left-hand corner of the bin and rotate deposits in a clockwise system.
    • We want to have soil all the way around the deposit
  • To begin, start off with smaller deposits. A deposit about the size of a medium grapefruit or softball would be great. Worms will reproduce quite quickly and therefore in about two months, you will likely have over a pound of worms in the bin. You ca, therefore, increase the amount of your food deposit.
    • Remember that worms will eat half their body weight a day in food but not all worms will be at that deposit site so you will be in essence feeding the worms in that area. Once you have put food in each deposit site the worms will have food available throughout the bin.
  • Take your trowel and scrape the soil from your excavated hole and cover the organic material deposit. You need to cover the deposit with at least 1 inch of soil. You can form a hump if need be.
    • It is important that no organic material (food) that you are putting into the bin is left on the surface. If you do you run the risk of attracting fruit flies and fungus gnats.
    • In essence and in practice you want to encapsulate the deposit with nice dark damp soil.
  • Take your marker (a chopstick works well) and stick it into the deposit. This will be a reminder to yourself or someone else where the last deposit was made and the next deposit will be made one deposit site over in a clockwise direction.
  • Deposit food in your second site 2-3 days after your first deposit. Continue to do so.

Harvesting the castings

Worms will eat all the organic material you are depositing and the bedding. Over time the level of their excrement (castings) will increase and will get to a point that makes the bin unhealthy for them. No organism lives in their own excrement.

If the worms had a choice they would pack up and move to a new environment that would be healthier for them but they can’t. Being the creator of their finite world you have a responsibility.

Over time you will notice the texture of the bedding in the bin change. It will get more pellet-like, will not hold onto moisture as well as it did and possibly not absorb odours as well as it use to.

It has been our experience that after about six months of the worms working their way through the worm bin eating the food AND the bedding it will be time to change out the bedding. We recommend that after you set up your bin that you mark on your calendar that in six months you need to attend to changing out the bedding and put in new fresh damp bedding.

In several of these methods, we use some of the worms characteristics to help make the worm sorting easier. Worms don’t like light (photosensitive) and they like food.

There are several ways to do this and the internet will show you several:

Divide and feed – Horizontal Method

We will use the fact that worms will move towards food and away from food sparse areas.


  • Worm bin
  • Fresh damp bedding
  • Supply of great worm food
  • Damp Burlap sheet (Take a burlap bag and cut so that it forms a single sheet)


  • Stop feeding your bin for a week. This gets rid of any food scraps and makes the worms hungry.
  • If you have enough space in your bin remove all the bedding from one-half and pile it on the other half.
    • If you wanted to be a little fancier about the separation you could put a damp piece of burlap between the two sides. This will nicely separate hold material on each side and the worms will work themselves through the weave. You can use anything with a loose weave to accomplish this. See below how else to use a fabric to help separate the worms.
  • Line the bottom of the emptied side with new fresh bedding of about 2 inches deep. Now put in some really good worm food – chopped up, decomposing, rotting, soft items. We want to make the food really enticing.
  • Fill up this side and cover it with fresh damp bedding of at least two inches.
  • In about 7-10 days most of the worms will have migrated over to the food side.
  • You should then remove the old bedding from the bin. (quickly go through it to see if there are any worms in it). This old bedding should be concentrated castings.

Light and Burlap – Vertical method

We are going to use the photo-sensitivity of the worms to help them migrate from the old bedding to the new fresh damp bedding.


  • Worm bin
  • Large sheet of plastic
  • Damp Burlap sheet – if using (Take a burlap bag and cut so that it forms a single sheet)
  • Light source
  • Container(s) of some kind for separated castings. Two 20 Litre pails usually works fine.


  • Dump your old bedding onto a large sheet of plastic.
  • Place the bin under a bright light or outside in direct sunlight.
  • Put new fresh damp bedding in the bin to within 3-4 inches from the lip.
  • Lay a damp burlap bag on the surface. Make sure the burlap is large enough that the edges are overhanging on the edges of the bin. You will be using the edges to lift the burlap.
  • Take some of the old contents of the bin and spread on the damp burlap bag so that you have about 1/2″ of old bedding sitting on top of the burlap.
  • Leave the bin for 15-20 minutes
  • When you come back sift through the old bedding to see if there are any worms left in the old bedding.
  • Slowly lift the burlap sheet from the new bedding. Look on the underside of it since there could be some worms in the process of squeezing themselves through. Help pull them through and put them into the new bedding material. This will give you an idea about how long you have to wait for the worms to migrate.
  • Repeat the process until you get through your pile of old bedding.
    • Caution – if doing this outside you can’t leave the worms alone for too long since the neighbourhood robins and other birds will gladly drop by to eat some of the worms close to the surface. As you get through your old bedding it might be good to have some kind of cover for the pile so as to protect the worms still remaining in the old pile. The worms in this pile will also be heading south – deeper into the pile to get away from the light and disturbance created by you pulling soil off the pile.

Pyramids/Cones, light and hand sorting

This is the classic separation method developed by Mary Applehof (the person that introduced worm composting to much of North America with her books and knowledge). Mary used the photosensitivity of the worms to help separate the worms from their castings.

This process usually takes us about three hours to do. If you have lots of little hands to help it makes it go a little faster. It can be quite meditative and relaxing to do this process.

An advantage of this process is that you will come across most of the worm eggs and therefore put them into the new fresh damp bedding.


  • Worm bin
  • Large sheet of plastic
  • Light source
  • Container(s) of some kind for separated castings. Two 20 Litre pails usually works fine.
  • Large working area


  • Lay out large plastic sheet under a light source (the stronger the better.
  • Dump old bedding on the plastic sheet
  • Form the old bedding into small cones/pyramids/piles/hills – about 6-8 inches high and the same across the base
  • Set up the bin with new fresh damp bedding to within 3 inches of the bin’s lip.
    • Some people recommend washing out the bin every time or every second time.
  • The worms will migrate to the base of the cones/pyramid/piles away from the light
  • Grab a handful of old bedding from one of the piles and look through it. Pull any worms that are slow and put into the new bedding.
    • Look for worm eggs and transfer these as well
    • The removed old bedding will expose more worms to the light and they will move away – deeper into the pile. You are using the light to herding the worms 🙂
  • Move to the next pile and repeat the process. This is where the meditation comes in. Repeat until your brain goes a little numb. It is relaxing.
  • When you get close to the base of the piles there are quite often a lot of worms amassed there. We normally don’t worry about the last little bit of old bedding but scoop up the worms and whatever there is left of the old bedding and put all of it into the new bedding in the bin.
  • Clean up
  • They will love you for all the care and attention but really they like to be left alone now.
  • Start feeding the worms in their new fresh bedding the next day

When we can out the bins we will quite often add a little bit of some kind of mineral product like Azomite, rock dust, or even dirt from the store. Worms need grit to digest food material passing through their stomachs.

What to do with Finished Compost – the Castings

Worms casting are the added bonus to this whole process. Beyond the benefits of reducing our personal contribution to the stream of organic material ending up in our landfill sites breaking we end up with an end product that is a wonderful soil amendment and fertilizer.

Here are some ideas on how to use the castings:

  • Mix worm castings with the same amount of potting soil and top dress indoor plants. If your plant pots are too full scrap off 1/2″ of the old soil and replace it with the casting/soil mixture.
  • Side dress or top dress outdoor plants.
  • If it is planting season you can sprinkle some in the soil troughs where you plant your seeds (Carrots, beets, radishes, etc).
  • If you are transplanting plants to the outdoors you can put some castings into the bottom of the transplant hole
  • Mix with potting soil to make your own germination/transplanting/potting soil blend.
  • Presents – pack up some worm poop in a 250mL, 500mL, or 1L mason jar and wrap them up for a most unusual but very useful present.


Worms are dying

Did you recently add lots of something? Did you add something toxic? If you did, dig it up and remove it.

Worms are climbing up the walls of the bin or on the underside of the lid

Do you have holes in the lid? How far away is the top of the bedding from the holes? Is it damp?


If the bin doesn’t smell like fresh earth there is something wrong. Did you put meat or dairy in it? Is there adequate air supply? Is it too wet? How long have you had the bin? Should the bedding be switched out?

Some interesting things about worms.

  • Worms are hermaphrodites – they have both male and female sexual organs in the same body. They still need to copulate with another worm to produce offspring.
  • Worms have 5 hearts which are also used as muscles around their ‘stomach’ to digest food and to circulate the blood around their bodies.

Earth’s General Store offers all of the tools and information to help you get your worm compost going.


In Alberta, the education system includes a unit called Waste and Our World for grade 4 students. Part of this unit is talking about landfills, recycling and composting. Many teachers purchase worm bins to set up in the class so there is a hands-on experience for the students.

Over the years we have developed a few suggestions for teachers to help with this module.

  • Worms don’t like to be overly disturbed so it is good to have one person doing the digging and depositing at a time.
    • Every week select a person(s) to be the worm monitor and their task is to do the food deposit on assigned days. We suggest that food is deposited on Monday, Wednesday and Fridays so you might have three worm monitors per week. This can be a useful teaching moment insofar that there will be an organisational system that the students need to participate in.
  • When you are off on holidays (long weekends, Christmas, Easter, etc) just put in extra food and ensure that the bin is moist
  • See above for details about maintaining your worm bin because in about 6 months the bedding in the worm bin needs to be changed out.
  • If you are going to let the bin go at the end of the year because you can’t or don’t want to care for the worms over the summer then we suggest that you pass it onto either a student that wants to do it at home (with their parent’s permission of course) or another teacher. There are always other teachers that are looking for free resources. If those options don’t work it can be distributed via Kijijii or Craig’s list.

School Resources

As an Alberta teacher, you will have the government’s module available for your class. The internet has lots of other resources that can complement your resources. There used to be people available through the school board to do in-service sessions on composting.

I do like this teacher’s guide from California and this article has lots of ideas on what aspects you can use worms in many different subject areas – maths. arts, social studies, etc.

The City of Edmonton and the John Janzen Nature Centre offers teachers an opportunity to have one of their Compost Chefs to visit your classroom. See their website for more details.

Ordering/Purchasing Worms

We no longer offer worms for sale at our store.

Dirt Willy Farm has been our supplier for the past 24 years. The owner died at the end of September. Please check out Kijiji to locate worms in Edmonton.

Here are some local people you can get worms from: