Blog Header: Healthy worm farms

A Guide for Happy and Healthy Worm Farms

This guide is republished from Sustainable Port Phillip. Read their other worm farm guides here

Where should I put my worm farm?

Worm farms require a shady spot, especially one that is away from the afternoon sun! Undercover spots including open sheds and outdoor areas with lots of tree cover are ideal.

Feeding time: do's and don'ts

Please note: Worm farms require a balanced diet with a 50:50 ratio of nitrogen (food scraps) and carbon (cardboard and paper).

Yes please:
✓ Chopped up fruit and vegetable scraps/peelings
✓ Crushed egg shells
✓ Tea bags/leaves and coffee grounds
✓ Ripped newspaper, uncoated (non-shiny) paper and receipts
✓ Ripped cardboard and eggs cartons
✓ Paper towel/tissues

No thank you:
× Citrus – oranges, lemons, etc 
× Onions (including leeks and garlic)
× Meat and dairy
× Pasta and rice
× Bread

Utilising the by-products: worm castings and worm juice

Worm Castings

  • Harvesting frequency: Every 8-10 weeks
  • Removal: Unclip the tray that is attached to the bottom of your worm farm (not the tray that is on the ground). Worm castings will look like moist soil.
  • Application: Mix with potting mix for use on potted plants or spread as mulch around plants.

Worm Juice

  • Harvesting frequency: As required
  • Removal: Worm juice will naturally filter through the worm farm into the drip tray underneath.
  • Application: Dilute the worm juice with water to a ratio of 1:10 (or until the liquid resembles a weak tea). Pour onto plants as a liquid fertiliser.

Keeping cool during hot days

Worm farms will need some extra TLC during hot days (≥30°C). We recommend utilising the below tips to keep your worms cool and happy in the warmer weather:

✓ Gently bury a frozen drink bottle deep into the worm farm
✓ Cover the worm farm in a wet blanket or towel
✓ Don’t feed the worms (processing food scraps creates heat)


1. I’ve put my worm farm in a spot that is partially shaded but I don’t know if it will be enough! 

If you are needing some extra shade for your worm farm, try installing a shade sail or outdoor screen. If the spot is shaded in the morning but very exposed in the afternoon it won’t be suitable.

2. My worm farm smells bad…

Bad smells often occur when you have overfed the worms and they aren’t able to process the food scraps quickly enough. Remove some of the food on the top, pour some water on the top to rise the worm farm and add some extra paper or cardboard on the top.

3. Why are there little flies (vinegar flies) around my worm farm?

Vinegar flies indicate that there are too many food scraps in your worm farms. Remove some of the food on the top of the worm farm and reduce the quantity/frequency that you are feeding the worms food scraps.

4. We are going away and no one will be able to feed the worm farm.

Your worm farm should be able to cope without any food for 3-4 weeks. Consider adding some moistened newspaper or pea straw before you go as the worms can break this down slowly.

Boon Wurrung Foundation Logo The EcoCentre acknowledges the Kulin Nations, including the Yalukut Weelam clan of the Boon Wurrung language group, traditional owners of the land on which we are located. We pay respects to their Elders past and present, and extend that respect to other Aboriginal and Elder members of our multicultural community.