Worm farming at home

Worm Factory.jpg

A worm farm is a self-contained home for worms where they break down organic matter into worm castings (vermicast); worm tea (leachate) is another output.

Worm farming can be a quick win for climate action as it removes organic waste from landfill where it can create methane (methane is about 25 times stronger than CO2 as a climate gas). You can harvest worm casting to feed your soil and make worms tea as a liquid fertilised for your indoor and outdoor plants.

What do I need to start a worm farm?

The equipment you need for a worm farm is pretty simple.   

  • Worm farm.  Can be purchased new or second hand. A purchased worm farm is great for kids, small families, homeowners, apartment dwellers and renters. Old bathtubs or laundry troughs make good DIY worm farms if you have a bit more space in your garden. 
  • Bedding e.g. a brick of coconut coir, cardboard
  • Composting worms (approx. 1,000). In Victoria these are usually red wrigglers or tiger worms. Material (organic) cover. This keeps the worm protected and helps keep the surface dark and moist.  It could be a purchased cover or an old piece of natural material (e.g. cotton, wool, cardboard) like a tee shirt, jumper, jeans, towel.

*Worm farms, worms and accessories are available for purchase at Edendale in The Shop.

**We also run free worm farm workshops.  Check out the events and workshops tab on our website for upcoming workshops.

A simple worm farming recipe

There is a simple recipe to follow to have a successful and productive work farm.  

Greens + Browns + Water + Worms = Worm Castings + Worm Tea


Greens are organic materials that have a higher Nitrogen ratio compared to Carbon. Worm farms are a little fussier than a compost.

Ingredients to add to your worm farm include

  • fruit and vegetable scraps
  • coffee grinds
  • tea leaves
  • crushed egg shells
  • small amounts of farm animal manure

Ingredients to avoid adding to your work farm are:

  • meat
  • dairy products
  • baked goods (cake, bread)
  • citrus or acidic foods
  • oils, fat, grease
  • bones


Worms love and need Browns as part of a balanced diet.  Add some when you add some greens,  A natural cover (hessian, cotton shirt, jeans) is also a carbon element and will be eaten over time

Brown materials that you can add to your worm farm include

  • dried leaves
  • straw
  • sugar cane mulch
  • sawdust
  • wood shavings
  • newspaper
  • cardboard,
  • natural material cover (hessian, cotton shirt, jeans) is also a carbon element and will be eaten over time

Brown material to avoid include

  • glossy paper
  • laser printed paper (e.g. bills)
  • any products treated with chemicals



Worms breath through their skin and need a damp environment to thrive. Generally worm farms get moisture from the fruit and veggie scraps but giving them a shower of water every couple of weeks is a good thing to do. It will wet their cover, give them a rinse and make some fresh worm tea. Use tank water if you have it as it will not have chlorine and other chemicals added.  Sprinkling 1/2 a watering can of water over the farm every couple of weeks also gives you a regular supply of fresh worm tea for your garden.



Worm farm worms are not the same as common garden earthworms. Worm farm worms have been chosen as they feed on the surface and can consume up to their own body weight in food every day.  In a temperate climate like Victoria the worm used are usually Tiger Worms or Red Wrigglers.
To start a worm farm you generally buy 1,000 worms, or maybe you have a friend that can gift you some from their own worm farms.  All mature worms can produce worm eggs / cacoons.  A worm can lay an egg every 7 to 10 days and up to 15 baby worms can hatch from a single cacoon. The worm population can double every 60 to 90 days 
This clip shows the biology of worms, their muscle rings and hearts pumping blood, the saddle with their reproduction organs, food going through their bodies and baby worms hatching from a cacoon



Worms do not like heat and a whole worm farm community can die if left in a hot sun for too long.Place the worm farm in a shady spot where it is sheltered in summer. although the worms do like some warming sun on the farm in winter.


Worm farm conditioners

Other ingredients you may occasionally add to a worm farm include

  • Finally crushed eggshells - adds calcium and grit for the worms to help with their processing of the food
  • Garden Lime - add a couple handfuls of garden lime if the worm is acidic or has vinegar fly's
  • Wood ash - is a homemade alternative to lime. Add if the worm farm is acidic or has vinegar fly's
  • Occasional sprinkle high protein chook mash as a treat (if you keep chooks)
  • Worm conditioner - there are commercially available conditioners to sprinkle over the farm which include lime and rock dusts to help worm farm health


A worm farm will work faster if the food (greens and browns) is cut smaller. Chopping ingredients creates more surface area for the microbes and worms to go to work, increasing the speed of processing meaning you can add more food more often. Larger fruit and veggies will still break down, but it will take longer. 

Setting up and operating a worm farm 

Worm farms need a cool spot in summer and preferably a warm spot in winter. This could be on the cool side of the house, in a carport or even in the laundry.  They are relatively low maintenance although there are some general guidelines to follow to keep them healthy and productive.

Setting up a worm farm

  1. A worm farm will have a solid base with a tap for accessing worm tea and a number of trays with gaps that the worms can move through. Start with the base plus a tray on top for their first home.  Store the spare tray till needed
  2. Place paper or cardboard over the slots of the empty tray (not the solid base) to stop bedding falling into the base.  Spread moistened bedding (e.g. soaked brick of coconut coir) over the cardboard
  3. Place the worms on the bedding and cover with a damp cover to create a dark, damp and safe place for the worms to live.  Leave them for a couple of days to settle in. Over time the cover will also get eaten as it is a brown (high carbon) material
  4. Add a cup of finely chopped kitchen scraps. Monitor how long it takes to consume 50%. There is no need to add Browns at this stage as the bedding is a Brown ingredient.
  5. Start slow, checking occasionally to add more kitchen scraps.  The worms will quickly grow and multiply increasing the amount of food you can add.  When fully operating there should not be more than 1 cm of unprocessed food scraps over the surface.
  6. Keep adding Greens and occasional Browns until the food tray is full.  Add the spare tray to the top and add food at this level (new bedding isn't required).  Over time many worms will move up into the new tray, leaving the old full tray free to harvest. Keep repeating the process


Maintaining a worm farm

  1. Place the worm farm in a cool place out of the hot sun. Some winter sun is OK
  2. Do not over feed. Once fully active there should be no more than 1cm of food over the surface
  3. Add food (greens and browns) till the tray reaches the full level.
  4. Add next tray on top (no need to add new bedding)
  5. Add food to the new tray, The worms will move up though the slots to the new food food
  6. Continue to fill the tray. When full, add another tray
  7. You can harvest the first tray when it is fully processed

Harvesting the worm castings (vericasting)

  • When the worms have finished processing a tray it is time to harvest the castings
  • There are likely to still be some worms in the tray so you may want to try and get as many out before you use the castings
  • Remove the tray and leave it in day light (but not too hot), or place it under a light
  • The worms will go towards the bottom as they don’t like light so you can then harvest the top section of the castings. 
  • Repeat till you have harvested most of the castings
  • Add the final castings plus the worms back into the active worm farm tray

What to do when the weather is hot

Worms do not like hot weather so if left in the sun you could have a disaster on your hands. In hot weather
  • Move into the shade e.g. into a garage, up the side of the house
  • Give them a watering of cool water
  • Place a wet towel over the worm farm to encourage cooling evaporation over the farm 
  • Place an ice block inside the work farm, on top of the material covering
  • Check to make sure they are faring ok


Using worm casting and worm tea

Using worm castings and worm tea in your garden will promote a healthy and productive garden. 

Using worm castings

There are a number of ways you can use your worm castings
  • Spread around root zone of plants.  Cover the castings with mulch immediately to stop the sun killing off the microbial life in your newly inoculated soil
  • Place a handful in the bottom of the whole when planting seedlings
  • Dig it into the veggie garden soil between crops
  • Add some to a stocking and soak in water to extract castings tea. It is a great liquid conditioner / fertilizer for the soil

Using worm tea

Worm tea is the exudate or excess moisture from the farm that captures nutrients from the worms and organic matter.   Worm team makes a great liquid fertiliser.
  • Fresh is best - the best worm tea is always fresh and is open to the air to breath. Avoid worm tea that is old or has been bottled for a long period of time as pathogens can grow in this environment and may have negative effects on plants and soil
  • Worm tea can often look dark like expresso coffee. Dilute if down till it looks like tea.  A rule of thumb often used is 1 part tea to 10 parts water
  • The diluted tea can be sprinkled at the root zone of plants or over the leaves
  • You can increase the amount of fresh tea extracted by occasionally pouring ½ bucket water over the worms



Worm farms for dog poo

Do not put dog poo in the worm farm that will produce casting and worm tea for your food garden. 
You can make or buy a a worm farm specifically for dog poo though. These are generally covered tubes installed in the ground under a tree or shrub. Add your dog poo, some compost worms and water.  Don’t add other veggies as the worms won't eat the dog poo.  Occasionally add some carbon (e.g. paper towel used to pick up the poo). When it is full add some soil in the top and move farm. As the poo decomposes into the soil it will feed the plants.
Note: do not add the dog poo after your dog has been wormed.  Wait about a week before starting again.


*At Edendale we sell the Enso Pet system, learn more about composting pet waste.

Some tips about worm farming

  • When the farm is well established, add a couple handfuls of browns when you add greens
  • Keep a container of Browns near the worm farm so they are always at hand 
  • Leave the worm farm tap open with a bucket underneath so you will always know when there is fresh worm tea to use. 


Why does my worm farm smell?

If your worm farm smells, remove any rotting food and slow down the feeding. You can gently aerate the bedding and add moistened newspaper to help counter the effects of overfeeding. A handful of garden lime or wood ash will also help reduce acidity. Make sure no meat or dairy is being added.

How do I stop pests invading my worm farm?

Insects like slaters, beetles, flies and mites are all a part of the natural decomposition cycle and are fine to have in a worm farm. You can place the legs of the worm farm in bowls of water to cut off their pathway.


Why are there flies in my worm farm?

If flies become annoying, reduce feeding and cover the surface with damp hessian or towel.


Can I use worms from my garden?

This is not recommended. Worm farm worms are chosen as they live on the surface with the food and can consume up to their own body weight in food every day making them perfect for a worm farm. Earth worms have different skills and prefer a different environment.  Do not put worm farm worms into the garden as the conditions are not suitable for their survival.


What do I do in hot weather?

Move the worms to a cool spot. If there are a number of hot days in a row you can drape a wet towel over the whole farm to keep it cool or add some ice blocks on top of the material cover.


Why are the worms trying to escape?

The worms may be trying to get out if the environment within the farm is not suitable. It could be too hot, too wet or there is too much food. Look at the farm a determine what is out of balance.  If too hot, move the farm to a cooler spot. If it has been over fed, remove excess food and add dry ingredients and add a handful of garden lime

Sometimes worms head to the top of a worm farm or compost if they sense it is going to rain. 

What happens when I go away on holiday?

Worms can live for months without fresh food. Feed larger cut Greens and lots of moist Browns before you go.


My worm farm seems to be dead. What do I do?

A worm farm can die for a number of reasons.  If it was too wet, too much food, too hot, too dry. It may be that some worms are still alive.  Try to rebalance the farm with the missing ingredients and be patient.  It could be that there are worm eggs in the worm castings that could hatch and repopulate the farm. It is important to address the reason for the tragedy so that any surviving worms / eggs can thrive.  If it is really bad you may need to start again. 


Free Edendale worm farming workshops

Edendale regularly runs free introduction to worm farming workshops. These are suitable for people new to worm farms, those that have some problems or questions about their current worm farm, or those that are worm farm curious.

Check out the Edendale Events and Workshops page for details of upcoming workshops.

Recording of Edendale Setting up a Worm Farm workshop