Vermicompost – Your Guide to Vermicomposting / Worm Composting

If you’re thinking of getting into worm composting, you’ve probably got a pile of questions, maybe even a little trepidation. Worm composting may seem like a strange concept, but it’s really just another form of composting. The worms are actually doing the work of breaking down your organic waste, and the end result is compost you can use to enrich your garden soil. If you’re looking to start a worm composting bin, here’s a quick guide to setting up your very own worm compost.

What is Vermicompost (Worm Compost) and Vermicomposting (Worm Composting)?

Vermicompost is Compost made from Worm casting.

Vermicomposting is the process of breaking down or composting organic matter using worms.

Vermicompost is much quicker and easier than traditional composting. This is due to the fact that a worm can eat their weight in organic matter everyday, and they leave behind a richer by product with more nutrients than other composting methods. 

You also get two beneficial products from your efforts 

  • Worm Compost – to be used as a soil conditioner or as a part of homemade growing media 
  • Liquid Fertiliser – Known as Vermicompost Tea or Worm Compost Tea

Some people refer to this method as Worm Composting. The worms also do all the work for you, no need to turn over the pile like traditional composting.

So do your part and stop sending your organic matter to the landfill. Instead create black gold for your garden, flowerbeds, or lawn. Your vegetables will taste better, your flowers will be brighter, and it is all completely organic, no chemicals. 

So how do you get started ? Well you need somewhere for this to happen, a Wormery or a Vermicompost Bin somewhere for the worms to live and get through the organic material.

Wormeries / Worm Composter’s / Vermicompost bins are odour free and compact and can be placed in the garage, basement, patio, or even your kitchen. This means no more cold or rainy walks to the compost pile.

wormery with cross sections

How a Vermicompost Bin / Worm Composter / Wormery Works

The best way to explain how a vermicompost bin works is to take you quickly through the system staring at the top and working our way down.

1. The Working Tray: This is the top tray in your vermicompost bin and usually has a  lid to protect the bin from light and rain, as well as from cats and birds. Inside this top tray you will have a sheets of newspaper of cardboard on the very top to hold in moisture, followed by a layer of bedding and then the organic matter which is placed in the bottom of this tray. Worms will begin to eat this matter as soon as you start to add it and they will hang out in the bedding when not feeding. After this tray is filled to capacity a new working tray is placed on top and your organic matter is placed in to this new working tray.

about2.Trays in Progress: These trays where at one time working trays that where filled with organic matter and bedding. In progress trays are allowed to mature in the middle of the bin as the worms eat the last of the food and bedding. After all of the food and bedding is consumed, they move upward towards the working tray leaving behind a tray full of vermicompost.

3.Harvestable Trays: After all of the organic matter is consumed, and the worms have moved out the tray becomes harvestable. These trays are found near the bottom of the bin and have been in the system the longest. To check if a tray is harvestable, just scrape through the tray with a hand rake and look for food, bedding, or worms. If the food and bedding are gone and the worms have moved on you are ready to harvest the vermicompost in this tray.

4.Runoff: During the vermicomposting process and when moist bedding is added to the bin, excess liquid can be generated. This liquid falls to the bottom of the bin and is collected in the base of the bin. This liquid is high in nutrients and beneficial bacteria and should be used as a liquid fertiliser, or added back to the top of the bin.

What Worms To Use

These are not earthworms, earthworms will not survive in the compost bin environment. Make sure to use composting worms. These amazing creatures are one long digestive system, and help nature break down organic matter in huge amounts. They will put your compost pile to shame. They can grow to 6″ in length, double their population every 3 months and eat their own weight in organic matter everyday. Composting worms are also known as tiger worms, brandlings, reds and dendras. 

How Many Worms do I need?

For the standard bin, with roughly two to three square feet of surface area, one pound of worms will be great. If you are using a larger bin, or want a quicker start up then use two pounds.

Composting Worms

Your Wormery

You can create your own vermicompost bin using a plastic container with a lid by drilling a lot of holes all over the entire bin. Next place a tray under the bin to collect any runoff. These bin work for light usage, and are better than the landfill, but for a efficient health system nothing beat a well designed bin. If you read “5 reasons to buy a bin” below and you still want to do it yourself, which I can’t blame you I am an avid DIY guy.

DIY worm composter / vermicompost bin video

5 Reasons to buy a Vermicompost Bin / Wormery:

  1. Air Flow: This is the biggest key to success for vermicompost bins. Good air flow eliminates odours and keep worms healthy which means faster vermicomposting. If you DIY make sure you have a lot of air holes, but nothing can beat the vent designs on vermicomposting bin systems.
  2. Ease of Use: Single bin systems require you to have elaborate plans of where to place organic matter and when to harvest which side. Then you have to scoop the vermicompost out by hand and problems after problems. Multiple tray systems are easy to use, load the top tray, and then pull the bottom tray out when it is ready to harvest.
  3. Speed: As mentioned before, these bins are optimised to provide the best airflow and keep your composting worms in the best of health. This translates into a faster conversion of your organic matter into vermicompost.
  4. Compaction: I started out using a DIY bin, and always had dead spots in my bin because of compaction and poor drainage. This is especially true in the corners of the bin and other spots that don’t get turned very often. These compacted wet dead spots lead to off odours. This in turn lead to me buying a vermicompost system.
  5. Smell: As mentions in two of the points above, smells come from poorly designed bins. Anytime you have compacted material, wet material, or spots that don’t receive enough air or drainage, you will get odours.

Starting your Vermicompost Bin / Wormery / Worm Composter

1. Shred your bedding materials. This bedding will mimics the leaf litter that compost worms are accustom too. It should a high carbon material that is light and loose to allow good air circulation.

Prefered Bedding Materials

  • Computer Paper
  • Junk Mail(Non Glossy)
  • Cardboard
  • Newspaper
  • Leaves
  • Straw
  • Sawdust

2. Fill the your bin half to three quarters full with bedding. Spray the bedding material with water and it allow to soak in. Check the material by grabbing a handful and squeezing. If water pours out of the bedding it is too wet, add more dry bedding and mix in. If you squeeze the bedding and a couple of drops come out of the bedding it is just right. After bringing the bedding to the correct moisture content, fluff the bedding a little to add some air. This will ensure happy, health worms.

3. Add a layer of soil to the top of the bedding. This will give the worms so grit, and help them to digest.

4. Drain any excess water from the bottom of your bin and then close back up the drain. The bin is now ready for your worms. Place the worms on top of the soil layer. Leave the lid of the bin, so that the ambient light will encourage the worms to dig into their new home. After the worms have dug into the soil, you can place the lid on top.


Adding Organic Matter to the Bin

Making sure that you are adding the correct type of organic matter is important to running a bin. Adding meats or dairy products will cause bad odours as they break down. Other bad organic matter like too much citrus, garlic, or onions will make your worms unhappy.

  • Vegetable Peelings
  • Fruit Peelings
  • Garden Scraps
  • Coffee Grounds/Filters
  • Tea Bags

1. Start in a corner of the bin. Dig a hole in the bedding, add your organic matter, and then cover with the bedding. To speed up the process, cut up your matter into the smallest pieces possible.

2. When you come back to add more matter, dig a hole next to the previous hole and repeat the first step. It maybe helpful to use a rock or other object to mark your last addition. Also as you add material, check to ensure that the bedding is the proper moisture content. If the bedding starts to dry out, sprinkle some water over top of the bedding. Make sure not to add to much or you will suffocate the worms, and create off odours.

When your first tray fills up with organic matter, add a second tray. This is done by adding bedding similar to the first tray and stacking it on top of the first tray. As the worms consume all the matter in the first tray, they will move up to the second tray.

Make sure to keep the bin out of freezing temperatures, direct sunlight, and excessive rain.Off odours are created by too much food, too much water, not enough air, or bad organic matter like meat or dairy. A healthy bin will not smell.

How to start a worm farming / worm composting / vermicomposting video


After the worms have had ample time to consume all the organic matter in the bottom tray or two of your bin, it is time to harvest.

1. Check the bottom tray of your bin, by digging briefly through it looking for worms and remaining chucks of organic matter. If there is a good amount of either, the tray is not ready yet for harvest.

2. To harvest simply dump or scoop the tray out and use the vermicompost (worm castings) where you would normally use compost.

Runoff Vermicompost Tea / Worm Tea (Liquid Fertiliser) 

The runoff from the bin is collected in a tray at the bottom of your bin and is usually accessible using a spigot. This runoff is high in nutrients and is a great liquid fertiliser. This liquid is also high in beneficial bacteria, so adding it back to the top of the bin will help increase the overall health of the bin. It is important to periodically remove this runoff to keep it from building up. Check it every couple of weeks and after adding water to the bin.

Different people have different ideas when it comes to vermicompost tea. I like to break vermicompost tea otherwise known as worm tea into three categories: 

  • Tea from the vermicompost bin / Wormery
  • Steeped vermicompost tea
  • Brewed vermicompost tea

If you are only interested in the nutrients in the vermicompost tea, then the first two types of tea work great. If you are looking to help prevent disease and increase the amount of beneficial bacteria in your garden, then brewed vermicompost tea is your best bet.

The brewed vermicompost tea is full of beneficial bacteria. This bacteria will help prevent diseases in the soil and on the foliage of the plant. Spray the tea over the soil and over the foliage of the plant to prevent diseases and help promote a health garden. For treating foliar diseases you should spray the vermicompost tea on the foliage of the plant. Reapply the tea every two weeks. Continue this treat to prevent diseases from coming back.

Tea from the Vermicompost Bin / Wormery / Worm Composter

When you add water the bin and during normal use there will be liquid that drains from the bottom of the bin. This liquid is caught in the tray at the bottom of the bin. This liquid is a great source of organic fertiliser and can be used straight from the bin .

I would recommend diluting this with water 1 part tea to 5 parts water. 

Steeped Vermicompost Tea / Worm Tea

Steeped vermicompost tea created by simply adding vermicompost to water and allowing it to steep in the water. Stir the mixture occasionally and allow to sit for at least 12 hours, but preferably two weeks. This mixture can then be strained to remove larger chunks that might clog watering cans,  screens and nozzles.

Brewed Vermicompost Tea / Worm Compost Tea

  • Bucket or Plastic Container
  • Aquarium Air Pump
  • Tubing for Air Pump
  • Airstone
  • 1 gallon of Vermicompost
  • Water (fill 5 gallon bucket up to 6″ from top)
  • 1 oz Unsulfered Molasses

1. Attach the tubing to the airstone and to the air pump. Then place the airstone in the bottom of the empty bucket. I suggest using a 5 gallon bucket for this, but if you want to use a larger container then you will need more air pumps, you should have 1 air pump for each 5 gallons. if the tea ever starts to smell bad, use the tea like a liquid fertilizer and start over using more air.


2. If you are using tap water, allow the air to bubble through the water for a day, then add the vermicompost. This step will allow the chlorine in the water to evaporate, helping to protect the beneficial bacteria in the vermicompost. If using rain water or other non tap water you can added the vermicompost immediately. Another helpful tip is to make sure you leave 6″ between the bucket rim and the water, otherwise the foam on top of the water might spill over the edge of the bucket.

3. Add 1 oz of unsulfurized molasses to the vermicompost tea. This adds a food supply, allowing the mixture to properly brew and create a healthy liquid filled with beneficial bacteria.

4. Keep the air on and allow the mixture to brew for at least 24 hours, 2-3 days is best.

5. Now that the tea is fully brewed you can strain it through cheesecloth. Add the solids that are strained out back to the vermicompost bin. This will help protect spray nozzles and other watering devices from clogging.

6. Now that your vermicompost tea is complete, use it immediately, or keep the air on until you are ready to use it.

Using Vermicompost / Worm Compost (Worm Castings) as a Soil Additive

For new beds or open ground, add an 1/8″ to 1/4″ layer of vermicompost / worm compost and work it into the top layer of soil. For poor soils work in as much as an 1″ of vermicompost into the top foot of soil.

For existing beds and gardens you can add a layer of vermicompost / worm compost to the top of the soil and allow the rain to slowly wash it into the soil. You can also dig small trenches around your plants and work the vermicompost into the soil as you backfill the trenches. Existing beds and gardens can also take advantage of vermicompost tea, which is talked about in the compost tea section of this website.

To improve your lawns soil you can add an 1/8″ to 1/4″ layer of soil over top of the lawn. For even greater results, you should see the top dressing section below.

Using Vermicompost / Worm Compost (Worm Castings) with Potted Plants

House plants will greatly benefits for vermicompost / worm compost. When planting or transplanting, simply mix up to 30% vermicompost in with your potting soil and plant as usual. You can also add a layer of vermicompost to the top of the soil for existing plants. Vermicompost tea may also be used for your periodic feedings.

Using Vermicompost / Worm Compost (Worm Casting) with New Plantings

When planting new trees and shrubs, work up to 30% vermicompost into the soil in the bottom of the hole, as well as when back filling. This will really get your plants established quickly.