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Worm farming uses composting worms such as tiger worms or red worms 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.

Getting started

  • Choose a cool shady site sheltered from the sun. Carports or sheltered porches are ideal.
  • Use a layer of bedding first – e.g. hay, coconut fibre, shredded cardboard or paper
  • Bedding should be damp and porous
  • Add worms – 1000 (250g) is fine; 2000 is even better
  • Worms can eat their own weight each day so don’t over feed them (e.g. 250g of worms give them about 200g of food)..
  • Worms need air but not light (photophobic) so cover food scraps with a damp carpet, newspaper or cardboard to provide a moist dark environment.
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What to feed your worms

Organic waste can be split up into two separate groups.

Greens Are

Organic waste that is full of nitrogen. It is usually soft, fresh and moist. Because of the nitrogen “Greens” rot and putrefy very quickly causing bad smells. Good examples of “Greens” are

  • Food waste
  • Fresh green lawn clippings

Browns Are

Organic waste that is mainly carbon. It is dry, brown and brittle. Because Browns are relatively free of nitrogen and moisture, they can take a very long time to breakdown. Good examples of “Browns” are

    • Fallen autumn leaves,
    • Paper and card board
    • Dry “browned-off” lawn clippings

Do add
Greens 70%

  • Most fruit and vege scraps
  • Coffee grounds and tea bags
  • Eggshells
  • Vacuum dust (natural carpet only)
  • Hair
  • Manure from animals like rabbits, & Guinea pigs

Browns 30%

  • Torn up, wet cardboard or paper
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Worms need 70% Green food and 30% browns

What NOT to feed your worms

Don’t 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
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Growing your worm population

How do you do this?

  • Add food scraps regularly, ideally every 1 – 2 days
  • Cut up the food you feed your worms. Make sure the pieces are smaller than a golf ball
  • Start with small amounts and slowly increase the food you give them over the first 6 months.
  • The population of worms will increase to match and will reach a point where they can eat through all the food waste you can give them very quickly
worm-farm-1

Harvest Time – Worm Casting

Worm castings

  • Worms feed at the top so harvest the casting from below
  • It is ready when the contents look like a dark fine compost and few worms can be seen.
  • Spread the castings around your garden beds.
  • Castings may be liquefied by adding one part castings to ten parts water and stir well
worm-farm-1
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Harvest Time – Worm Tea

Worm Tea

  • Always let the liquid drain off freely into a separate bucket. If your worm farm has a tap, leave it open.
  • Worm Tea should be diluted to the colour of weak black tea (1:10)
  • Apply 2-4 weeks around plant roots as a nutritious fertiliser
bokashi-7

There are two types of worm farms

worm-farm

Stacked worm farms are divided into different layers.

They usually consist of

  1. A sump- this collects the liquids. Always leave the tap open with a bucket underneath to allow the worm farm to drain
  2. Frames- Usually two. These are stacked on each other as the worm farm fills up.

How to Use

  • Place the sump on a stand, with a bucket underneath the tap to catch the liquids
  • 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
  • Over the next 6 months incrementally increase the food you feed your worms to build their population
  • When your first frame of worms is full add another frame on top.
  • The worms will move to the upper frame and will feed on the fresh food placed there
  • When this top frame is nearly full you can harvest the castings from the frame below.
  • Take away the lower frame and place the top frame directly on the sump.
  • 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

  1. Continuous flow worm farms are generally a single vessel with a large open cavity that houses the worms.
  2. It is secured at the base to hold the castings in place but still allows air to circulate and liquids to drain through.
  3. You simply feed on the surface and harvest from an opening at the base.
continuous-flow-barrel

How to Use

  • Fill the bottom quarter of the cavity with moist bedding and add your worms
  • Feed a small amount of food to your worm
  • Cover with wet carpet, paper or cardboard
  • Over the next 6 months incrementally increase the food you feed your worms to build up their population
continuous-flow-bag
  • Once the cavity is approximately two thirds full of worm castings you can start to harvest the compost through the opening at the base.
  • The majority of worms will remain in the upper areas to feed on the available food,
  • The castings will be quite compacted so should be free of worms
  • Liquids will drain through naturally and can be caught in a bucket placed under the body of the worm farm for use as Worm Tea

Six Common Worm Farming problems

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

Worm Farm Quiz questions and answers

Worm Farm Quiz questions and answers