Send in the Worms

This is a summary of information presented during February’s Starting a Worm Farm workshop at the NLFG.  During the workshop we set up a large wheelie bin worm farm, a domestic ‘Can of Worms’ farm and a budget polystyrene box farm.  Worm farms can be created in almost any container, as long as it has a source of drainage and a lid.

Getting Started

Worms can be sourced from the wormfarms/compost bins of friends or purchased from your local nursery or hardware supplier, although they are quite expensive to buy.  There are several species of composting worm that live in the mulch layer of gardens, towards the surface.  They differ from the earthworm, which lives lower in the soil, and composting worms and earthworms each perform a different function in the garden eco-system.  You need about 1000 worms to get started with your worm farm (at least 4-5 good handfuls of worms), although smaller numbers will work (it will just take longer for your farm to operate most efficiently).

In worm farms with holes in the bottom (domestic commercial farms, polystyrene boxes), you will need to cover the holes with several layers of newspaper, some hessian or piece of flyscreen.  This allows moisture to run through, but stops your worms falling through the holes.

All worm farmers need to establish a ‘bed’ for their worms.  The bed can be made from straw/mulch/hay/coir (coconut husk) or newspaper.  This material should be wet, but not dripping.  We added our worms to a bed of coir and shredded newspaper with good quality compost and worm castings in a layer that was about 4-5 centimetres thick.  You can also add manure or clean garden soil to help make your worms happy in their new home. 

Cover the worms and ‘bed’ with a ‘doona’ of thick newspaper, thick hessian layer or old carpet.  This layer needs to be moist but not dripping and should stay moist at all times.

Worms need 1-2 weeks to settle into their new home before you begin to feed them anything else.

Feeding your worms

After 1-2 weeks start by feeding your worms about a cup of food scraps and see how long it takes the worms to eat these.  You can gradually increase the amount of food that you feed your worms as the population increases and your farm begins to operate more efficiently.

Worms will eat all fruit and vegetable scraps and peelings except for citrus peelings and onion.  Things like corn cobs, avocado skin, and large seeds or pits are also unsuitable for the worm farm.  They will also eat other food scraps including bread, but do not put dairy or meat into the worm farm as these tend to smell and attract vermin.  Worms will also eat eggshells, however my experience is that these can often be left in the worm farm after other scraps have disappeared.

Worms particularly love coffee grinds and will also eat things like teabags, hair and vacuum cleaner dust.  I also like to add a bit of newspaper or straw mulch to the mix occasionally.

Worms have no teeth and find it tough going to munch on large food pieces.  Farms work most effectively when food scraps are cut into small pieces (about half a thumb size).

The food scraps should not rot in the worm farm.  If they are rotting, rather than being eaten, there is too much food being added to the farm.

Keeping it cool

The worm farm ‘doona’ of newspaper, hessian, cardboard or old carpet needs to be kept moist at all times.

Worm will die if they are too hot and farms should be stored in the shade.

On hot days (over 30°C) pay particular attention to keeping your farm cool.  Covering the entire worm farm with damp fabric/hessian/carpet ‘air conditions’ the farm and stops the worms dying.

The Good Stuff – Castings and Worm Juice

Worm castings are beautiful, smooth, rich dark brown worm ‘manure’ that are left in your worm farm as the worms munch through your waste.  They are nutrient-rich and spoonfuls can be added to your potted plants, in potting mix as you pot up new plants or sprinkled around the base of plants in the garden.

Worm juice will collect in the base of your worm farm surprisingly quickly and needs to be collected regularly.  Dilute worm juice at a ratio of 1:10 (the colour of weak tea) and use as you would a liquid fertilizer.  It will burn plants if not diluted.

To harvest worms in a domestic farm (such as our Can of Worms), create a new worm bed in the spare tray and place it on top of the layer full of castings.  The worms will migrate up to their new bed over a week or so, leaving the bottom tray full of beautiful castings (and not many worms!).

In a box worm farm (or fridge or bathtub farm), move the worms’ castings and bedding to one side of the farm and add fresh bedding to the empty side.  Wait a week and most of the worms will move across to the fresh side, leaving the castings and old bedding for you to collect.

Possible Problems

Your worm farm should not really smell.  If it smells, food is rotting in your farm and you need to put in less food.

Small flies/insects can often infest your farm.  Sprinkling a good handful of garden lime in your farm once every 1-2 months will make them go away.  This can also be another indicator that you are leaving too much food.

Your worms will leave if the environment is too acidic.  A handful of garden lime will neutralise the environment.

The easiest way to kill your worms is by letting the worm farm dry out (it needs to be moist at all times to keep worms’ moist bodies happy) or cooking the worms in the farm on hot days.

Worms will also drown if you forget to drain the liquid regularly, or they are exposed to the elements in a large down pour.

Any other questions or comments?  Leave your thoughts below.

Presented by Allison