Worm Farming
Worm farms are great for balconies and gardens – some people even keep theirs indoors! No meat, dairy, citrus or spicy foods though.
What is worm farming?
In a worm farm, tiger worms or red worms are used to eat through a mixture of food scraps, garden waste, waste paper and cardboard to produce worm castings (composted material) and liquid fertiliser, known as worm tea. Both the castings and the worm tea are excellent fertilisers and great for the garden.
Worm farming could be for you if:
you want to compost your food scraps at home, and keep the goodness local
you would like to complement a system you already have – be it the kerbside food scraps collection or Bokashi
you don’t have the outdoor space to compost
Get Started
Choose a cool shady site sheltered from the sun to set up your worm farm – carports or covered porches are great. Prepare the worm farm with a layer of damp, well drained and porous bedding, such as coconut fibre, shredded cardboard, or paper.
Add worms – 1000 (250g) is fine; 2000 is even better.
Cover food scraps with a damp carpet, newspaper or cardboard to provide a moist dark environment. Worms need air but not light (photophobic) to work their magic.
What to feed your worms
Organic waste can be split into two separate groups – greens and browns.
Organic waste full of nitrogen is a ‘green’. The nitrogen makes greens rot quickly, and smell unpleasant. Greens are usually soft, fresh, and moist, including food scraps and fresh lawn clippings.
A ‘brown’ is organic waste full of carbon. These are normally dry and brittle, and take a long time to break down as they have little nitrogen. Browns include fallen autumn leaves, dry “browned-off” lawn clippings, and cardboard.
Worms need roughly 70% green waste and 30% browns.
What to add:
Most fruit and vegetable scraps
Ground coffee and tea leaves
Manure from herbivorous animals like rabbits and guinea pigs
Torn up wet cardboard or paper
What not to add:
Spicy food
Chilli, onion and garlic
Meat and milk products
Bread and pasta
Cooked or processed food
Citrus or acidic foods
Oils and liquids such as soup
Stacked worm farms
These are divided into different layers – a sump which collects the liquid, and frames (usually two).
How to set up a stacked worm farm:
Place the sump on a stand, with a bucket underneath the tap to catch the liquid (keep the tap open to allow it to drain)
Place a frame on top of the sump
Fill this first frame with moist bedding and add your worms
Feed a small amount of food to your worms
Cover with wet carpet, paper or cardboard
Start by feeding your worms with small amounts, and slowly increase this over the first six months. The population of worms will grow to match the amount of food and will eventually reach a point where they can eat through all the food waste quickly. Feed your worms regularly, ideally every one to two days, and cut the food up to pieces smaller than golf balls for quicker and easier decomposition.
What to do when your worm farm is full:
When your first frame of worms is full, add another frame on top. The worms will move to the upper frame and feed on the fresh food placed there
When this top frame is nearly full you can harvest the castings from the frame below
Use the contents from the full frame on your garden or pot plants
Rinse and store this empty frame until your worm farm is ready to take another top frame
Continuous Flow Worm Farms
Continuous flow worm farms are generally a single vessel with a large open cavity that houses the worms.
It is secured at the base to hold the castings in place but still allows air to circulate and liquids to drain through.
You simply feed on the surface and harvest from an opening at the base.
Vermicast
Vermicast, otherwise known as worm castings or vermicompost is the product of the decomposition process. It is effectively worm manure, and is a fantastic fertiliser for plants.
Worms feed from the top, so you will find the vermicast in the lower trays of your worm farm. You will know when it is ready to harvest – it will look like dark fine compost or soil, and few worms can be seen. Once ready, spread it as is on your garden beds, or make a liquid fertiliser by adding one part vermicast to ten parts of water and stir well.
Worm Tea
Worm tea is the liquid that comes off your worm farm. This should always drain off freely into a separate bucket. If your worm farm has a tap, leave it open.
Worm tea can be diluted with water, one part worm tea to ten parts of water. It will be the colour of weak black tea.
Add this around your plants every two to four weeks as a nutritious fertiliser.
Problem 1 - Rotting food
Cause: Too much for population
Solution: Feed Less food
Problem 2 - Fruit/vinegar flies around farm or small white bugs and worms
Cause: Too acidic
Solution: Cover food with damp paper add lime to increase pH
Problem 3 - Worms climbing up side, worms very fat and pale
Cause: Too wet, check sump is not overfull of tea
Solution: Add paper products and dry leaves, gently fork holes in the working layer
Problem 4 - Ants
Cause: Too dry or acidic
Solution: Add water/lime, if your worm farm is on legs, place each leg in a container of water to stop such pests for getting in
Problem 5 - Food not eaten
Cause: Too much food/wrong food/ pieces too big
Solution: Add less food, break into small pieces, avoid bread, citrus, onion skins.
Problem 6 - No worm tea
Cause: Not enough water
Solution: Add water
