Worm Farming

Worms happily eat food scraps and excrete valuable materials known as vermicasts and worm tea, which are high in nitrogen, phosphorous and potassium (NPK) compared to ordinary soil.

The benefits of worm farming include:

• Casts and worm tea are fantastic for plants.
• If you have mostly kitchen waste and live in a home with little or no outdoor space, a worm farm is a good option.
• It has the same environmental and cost benefits as composting.
• Kids enjoy tending to worm farms.

Mitre10 has a guide to starting a worm farm as well as links to buy any products you may need. 
How to set up a worm farm - Easy As Gardening Guide | Mitre 10

Types of worm bins

Bins generally have two to three layers. Some bins can have extra layers added to increase capacity; however, it is easier to harvest worm casts from bins that have more shallow layers. Size, price and functionality vary a lot, so ask lots of questions before you buy!

What do works like to eat?

• Moist fruit and vegetable scraps
• Coffee grounds and tea bags
• Aged horse manure
• Dirty paper
• Crushed eggshells
• Vacuum cleaner dust
• Hair

What don't worms like to eat?

• Spicy food, chilli, onion and garlic
• Meat and milk products
• Flour products
• Large amounts of cooked food
• Garden waste
• Shiny paper
• Citrus/very acidic fruit

Things you need to know to get started

How many worms do I need to start?
A bin of worms take some time to get going so start with around 1,000. Starting with 2,000 worms (500 grams) will get a bin working more quickly and efficiently.

What if there are lots of fruit flies?
Add a decent sprinkling of lime and wait a day or two. If you still have flies, add more lime and carbon material (e.g., paper or dried leaves).

Do I need to lime my worm bin?
A small handful of lime or gypsum once a month helps to keep the food sweet.

What do I do if I go on holiday?
Add to the bin as follows:

• One to two weeks - empty out your fridge of any fruit and vegetables
• Two to three weeks - dried grass or coconut fibre from a garden centre or worm grower
• Four+ weeks - coconut fibre block from garden centre or worm grower.

How much do I dilute the 'worm tea'?
Worm tea is high in nitrogen and needs to be watered down to about 1:10 ratio, or so it is the colour of weak tea. The liquid is so rich that it can be harmful if not diluted.

What can I do with the worm casts?
Worm casts can be mixed with potting mix, seed raising mix and compost (about 20% casts to 80% mix), and is the perfect medium into which to plant seedlings, plants and trees. Casts do not have to be diluted for use in the garden but make sure they are mixed in to the soil. For best results, add compost and mulch as soil cover.

Common worm farming problems