Worm Farming 101

Worm Farming 101

Composting worms vs Earthworms

Though similar in appearance, compost worms are not earthworms.
  • Compost worms are generally smaller than earthworms.
  • Compost worms do not live in the soil, they feed above ground on organic waste and convert it into castings.
  • Earthworms feed on microorganisms and organic matter in the soil and help build soil structure.

Setting up your worm farm

Worm farms can come in many different shapes and sizes, from a bucket to a large scale food waste system.
  • A worm farm should be insulated/temperature controlled.
  • Always use a lid to help with insulation, keeping out the rain, and protection from rodents and predators.
  • Ensure it can drain out of the bottom.
  • Ensure there is an air pocket at the bottom or some airflow.
  • Worms need moisture, use mulch or a breathable material such as an old towel or pillowcase on top of the worms.
  • Before adding worms ensure they have adequate bedding using leaf litter or shredded paper.
  • Place the worm farm in a shady spot. Some morning sun if fine, but avoid hot mid- day and afternoon sun, especially in summer!

Feeding your worms

  • Do not overfeed your worms! This is the main reason a worm farm fails
  • Feed your worm; coffee grounds, leafy green scraps, vegetable scraps, a small amount of fruit scraps cut into pieces. Carbon marterial; dry leaves, shredded paper, cardboard, etc.
  • Do NOT feed your worms; citrus, processed food and bread, chilli, onion, garlic, meat, dairy or anything oily.
  • A well maintained worm bin should have a pH measurement between 6.0 and 7.0
  • Cut up the food as fine as possible
  • Feed worms about once every week or two. Or until the previous food is mostly gone. Worms are more active in warmer weather

Worm castings

Worm castings are one of the best natural fertalisers. Not only are they loaded with plant available nutrients, they are also full of beneficial bacteria and microorganisms. They are particularly useful used directly when planting out new trees or seedlings. They can also be mixed with soil, sand or other compost to enrich it.

Worm Tea

  • Worm tea is made by using a 'teabag' by placing worm castings into a stocking or cheesecloth then ‘brewing’ it in a bucket of water.
  • The tea needs to be aerated. The best way to do this is to use an aquarium pump. It can also be done by hand if you stir the brew every couple of hours.
  • The brew takes around 12 hours depending on the temperature, and potency of the castings. Molasses may be added to increase microbial activity but it is optional.
  • Once finished the brew should be used as soon as possible as a foliar spray or mixed with water and applied as a liquid fertiliser. 
  • If it smells bad don't use it! This normally means it has turned anaerobic and could contain harmful pathogens. 


Note! The water under your wormfarm is not the same as a worm tea, it is called worm leachate. While generally safe and beneficial to use in the garden, leachate can contain harmful pathogens. Again, if it smells bad, don’t use it!

Back to blog

Leave a comment

Please note, comments need to be approved before they are published.