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Hungry Bin – The Best Compost Bin

Neatly packed in an easy to carry box, the hungry bin is fast and easy to put together. Assembly instructions and a comprehensive instruction manual are included. Before you know it, you’ll be processing up to 2kg (4lb) of organic waste per day in the best compost bin available.

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Why The Hungry Bin is the Best Compost Bin

The hungry bin is a clean, simple and easy way to dispose of organic waste using compost worms. The hungry bin is designed to create an ideal living environment for compost worms. The worms convert the organic waste into worm castings and a nutrient-rich liquid, which are both high-quality fertilizers. It is easy to collect both the castings and liquid produced by the hungry bin.

The hungry bin can process up to 2kg (4lb) of organic waste per day. The waste is placed into the top of the bin, where the worms eat it as it softens and begins to decompose. The compost worms used in the bin are a different species from earthworms. Compost worms are surface feeders and prefer to live in organic material or mulch. They do not burrow into the soil like earthworms.

As the compost worms eat the waste in the bin, they convert it into worm castings. The castings are pushed down through the bin and compressed by the weight of fresh castings above them. The compressed castings are retained in the lower part of the bin, where they can be simply and easily removed when needed for use as plant food or soil conditioner. In normal operation, the castings will need to be removed from the bin once every two to six months.

Liquid drains down through the bin and passes through a filter housed in the floor, into the drip tray. This liquid is an ideal fertilizer. It is best to dilute the liquid with water before feeding it to plants, as it is very concentrated. A good dilution ratio is 1 part worm liquid to 10 parts water.

Please note for our customers in cold weather environments, it is recommended that the hungry bin be located indoors during the winter months in a mild, protected location such as an enclosed garage, basement or insulated shed. In summer months maximize the hungry bins productivity by ideally choosing a sheltered, shady spot – the ideal temperature is between 15-25 degrees Celsius (60-80 Fahrenheit). Avoid extremes of temperature, particularly full sun in summer, as temperatures over 35C (95F) may kill the worms. You can wheel your bin between different locations depending on the weather conditions or season. If the bin is outdoors in winter, make sure it is not subjected to freezing conditions for extended periods of time.
Step 1

Remove the parts from the box.

Step 2

Assemble the frame by sliding each leg through each side of the axle assembly, starting from the bottom end of each clamp. Push each leg through the clamp until the clamp is positioned at the start of the bend in the leg.

Step 3

Make sure the wheels are touching the ground when the legs are in an upright position. Using the hex key supplied, evenly tighten the 4 screws on each axle clamp to firmly secure the clamp to the leg. Tighten the screws in stages to ensure the gaps between both sides of the axle clamps are even.

Step 4

Place the lower body upside down on the ground. Insert the two latches into either side of the skirt of the lower body. The latches require a firm downward push to locate in position. You may find it easier to push the latches down with a screw driver, or gently tap them into place with a hammer.

Ensure the latches have clicked securely into place.

Step 5

Insert the top of the assembled legs into each of the lower body. Make sure the legs are positioned so that the wheels are on the same side as the latches. Push the legs firmly into the sockets.

Step 6

Place the Filter into the bottom of the Floor.

Step 7

Turn the lower body over to an upright position. Slide the floor with the filter inserted over the lower part of the lower body and lock into place with the latches. Press the centre of the red latch with your thumb to lock the latch into place.

Step 8

Place the upper body into the lower body.

Make sure the handle is positioned on the same side as the wheels.

Align the bottom of the locking tab at the rear of the upper body with the matching slot on the top of the lower body.

Step 9

Slide the rear tab into the matching slot in the lower body.

Push the upper body downwards on a slight angle until the bottom of the side tabs is aligned with the lower body slots.

You do not need to push the tab downwards until it locks in place at this point.

Step 10

Tilt the upper body down until the bottom of the two side tabs are aligned with the matching slots on the top of the lower body. You may need to pull the tabs outwards so that they line up with the slot.

Once both tabs have aligned with the slots, you can push the upper body down until the bottom of the front tab is aligned with the top of the slot.

Step 11

Align the front tab in the same manner as the other tabs and once all the tabs are located.

Push the upper body down until all the tabs have locked over the hooks on the side of the lower body.

You should hear a click as the tabs locate and lock in place on the hooks that are on the side of the lower body.

When completed wheel the hungry bin into position and place the drip tray underneath.

Congratulations, your hungry bin is now assembled and ready to start.

Getting Started?

- Place moist bedding material in the bin
- Start with at least 500 grams of live worms
- Add finely chopped food scraps
- Cover with hessian sack or damp newspaper

Bedding material is needed to settle the worms into their new home. Compost, soil, potting mix, coconut fibre, dead leaves or shredded paper can all be used to bed the compost worms into the bin. Take care to ensure that the bedding material you use to start the bin is free draining. Place the bedding material directly into the bottom of the bin.

For best results place at least 80 litres of bedding (3/4 Full) into the bin. This is the equivelent of two bags of compost or potting mix.

If you have sufficient bedding material available, you can fill the bin to the top of the taper before you add the worms.

Moisten the bedding material with some water, but don’t saturate it. The bedding should be as wet as a wrung-out sponge. Add the worms to the top of the bedding material and cover with approximately 2.5cm (1in) of food scraps (preferably finely chopped). The amount of food you add each day will depend on your starting worm population.

Approximately 2000 adult worms (or 500gms) is a good number to start your bin. However, the more worms you start with the faster the bin will reach maximum capacity. A full population is approximately 16,000 worms, or 3kg (6.5lbs) of adult worms.

It takes about six to eight months to breed a full population from a small starting population. As the population grows it will regulate its numbers to match the food supply. Your bin will not become overpopulated. The number of worms in the bin will be determined by the amount and type of food you feed the bin. Similarly, there is no minimum amount of food you need to feed the bin each day. As long as the bin is fed regularly, and you follow the feeding guidelines, the bin will operate without problems.

You can cover the worms with damp newspaper, sacking or old carpet to encourage them to come to the surface. Keep the lid closed as worms don’t like direct light – the lid is also designed to prevent insects from getting into the bin.


Choosing a location

- A sheltered shady spot is best
-Can be moved easily to a different location

Ideally choose a sheltered, shady spot for the hungry bin ­– the ideal temperature is between 15-25 degrees Celsius (60-85F). Avoid extremes of temperature, particularly full sun in summer, as temperatures over 35C (95F) may kill the worms. The bin can be kept on a balcony or in a garage or basement if you don’t have a garden. You can wheel your bin between different locations depending on the weather conditions or season. If the bin is outdoors in winter, make sure it is not subjected to freezing conditions for extended periods of time.

Moving the bin

Take care when moving the bin. When the bin is full of castings, it can weigh up to 125kg (275lb). If the bin accidentally tips over and lands on you when you are moving it, a serious injury may result. Lean the bin over about 15 degrees and balance it on its wheels before attempting to move it. Take care not to slip or lose your balance. Ensure that you have a firm grip on the handle and a secure footing. Take particular care if you are moving the bin over rough ground. Do not move the bin on slippery surfaces. Do not move the bin sideways on steep slopes or down stairs.


Compost worms benefit from a balanced diet. They will eat most normal kitchen fruit and vegetable scraps. Avoid feeding the worms large quantities of meat, citrus, onions and dairy foods. Some processed food also contains preservatives, which discourage the worms from eating it. These foods won’t harm your worms, but they will avoid them and those scraps will break down and rot in the bin. The worms will eat their preferred food first but like to have some variety. The smaller and softer the scraps, the easier it is for the worms to digest and process them into castings.


- Most fruit and vegetable scraps
- Pulp from the juicer
- Cooked food
- Tea leaves/bags and coffee grounds
- Crushed/ground eggshells
- Hair, vacuum cleaner dust, soiled paper, tissues, handy towels, shredded egg cartons, toilet roll inners, paper lunch wrap
- Shredded moist newspaper & cardboard
- Lawn clippings in small quantities (spray free), weeds, clippings, prunings, dirt and leaves
- Sawdust (untreated), wood ash


- Citrus, acidic fruit skin
- Spicy foods, onion, garlic, leeks, capsicums
- Meat and dairy products
- Bread, pasta and processed wheat products
- Shiny paper
- Fats or oils

Compost worms will also eat garden or yard waste, and animal manure. If adding lawn clippings take care to only add a little at a time. Fresh lawn clippings can heat up and cause problems. If you do place animal manure in your bin ensure that the animals have not been treated with anti-worm medication, as it may still be effective in their dung!

It is also not advised to use dog or cat droppings if you intend to use the castings in your food garden, as the animals may have gut parasites, which can potentially infect humans.

How much to feed worms

- Add up to 2.5cm per day
- Uneaten food should not be more than 5cm deep
- Only add more food as it is eaten

It is very important that the hungry bin is not overfed. A fully functioning bin will have up to 3kgs (6.5lbs) of compost worms. They prefer to eat their food as it begins to decompose, but not if it has become slimy and smelly. If the bin is overfed, the food scraps will begin to rot before the worms can eat them. Rotting food scraps not only smell, but also interfere with the lifecycle of the worms and the operation of the bin.

Rotting food is anaerobic – or oxygen deprived. Because worms breathe through their skin, anaerobic conditions prevent the worms from breathing properly, and may cause them to die.

Worms can eat roughly their own body weight in food a day, so make sure that you only add about the same volume of food each day as there are worms. Start by feeding the worms a small amount of food each day. Each time you feed the bin, check that uneaten food is not accumulating. You could chop up large food scraps into small pieces – the smaller and softer the scraps, the easier it is for the worms to digest and process them into castings.

Slowly increase the amount you feed the worms as the population multiplies. The worms will breed and increase in numbers to match the food supply. Building up a full population of worms (about 3kgs) can take up to six months.

Remember the hungry bin is not the same as a rubbish bin. A garbage truck does not magically empty it every week! The worms cannot eat the food as fast as it is possible for you to put it in, especially if the population is small when you start. It is better to underfeed your worms than overfeed them.

A good rule of thumb is that uneaten food should be no more than 5cm deep. You can check this by digging through the top layer of the bin and checking how deep the uneaten food is. In a healthy bin finished castings should be present 5-10cm (2-4in) below the top layer. You should also be able to see a mixture of adult and juvenile worms, indicating that the worms are breeding. If uneaten food is building up, simply stop putting new food into the bin until the worms have eaten the food present.

Approximately 20cm (8in) below the surface the food should have been completely converted into worm castings. Finished castings look like high quality compost and have very little smell.

Worm eggs should also be present in the castings immediately below the food layer; signifying conditions are ideal for breeding. The worms need to be able to lay their eggs in fresh castings immediately below the food they are eating. If the bin is overfed and a layer of rotting food has formed, the juvenile worms will be unable to move upwards through the rotting layer to the fresh food when they hatch, resulting in the population declining.

To remedy a build-up of rotting scraps, you may need to gently fork a small amount of fibrous material (See FAQ 3) into the top food layer. In extreme cases the rotting food will need to be removed completely and the bin restarted, as rotten food can take a long time to break down in the bin.

Harvesting Castings

Castings should only be harvested when the bin is full

Castings should only be removed when the hungry bin has become full to the top of the taper. Removing castings before the bin is full will affect how much food the bin can process. The hungry bin needs to be at least ¾ full of finished castings to work most efficiently. This is to ensure the finished castings in the lower part of the bin have been cured completely, and are fully compacted. When the floor is removed, the shape of the bin means only the castings in the bottom part of the bin will fall out. When the castings have been properly compacted and had enough time to consolidate, they are largely free of worms and clump together, making them easy to remove and handle.

If the floor is removed before the castings have become properly compacted, all the material present in the bin, including the worms, will fall out.

How to harvest castings

1. Remove the drip tray and pour any liquid there into a suitable container.
2. Release the latches securing the floor to the lower body.
3. Lower the floor from the bottom of the bin. The floor should be full of finished castings.
4. Tip the floor upside down and tap sharply to knock out finished castings.
5. If needed, clean the filter with a hose or some water.
6. Replace the floor over the lower body and secure in place with the latches.
Some worms may be present in the castings. The worms can be easily separated from the castings by spreading them on the upturned lid, and placing it on top of the bin. The worms present will retreat from the light deeper into the castings and the top layer can be removed. The separated worms can then be tipped back into the bin.

Plants have evolved to uptake the nutrients created by worms – their castings are one of the most beneficial fertilisers for plants. Castings are pH neutral, so are very safe to use with all plants. Even a small amount of castings or liquid added to soil will improve the performance of plants.

They can be used in the same way you use compost, or heaped around plants. Pure castings may burn the roots of small plants if used undiluted. For use on smaller plants it may be necessary to mix the castings with other soil first.

Getting the most out of your bin

The hungry bin is a living ecosystem. It is important that ideal conditions are maintained in the bin for it to operate most efficiently. Maintaining ideal conditions in the bin is easy – simply follow these basic rules:

1. Feed the bin a maximum layer of 2.5cm (1in) at any time

Do not overfeed your hungry bin. Spread the food evenly over the top layer of the bin. You should not feed the bin more than 2.5cm (1in) per day.

2. Uneaten food should be no more than 5cm (2in) deep at any time

Do not allow uneaten food to build up in the bin. If uneaten food has accumulated, it will begin to rot. Rotten food is acidic and putrid, and worms will not eat it.

3. Add fibre and/or lime occasionally to help balance the acidity of the bin

Adding some fibrous material such as shredded paper or cardboard, dead leaves, sawdust, old grass clippings (brown) or a sprinkling of lime or wood ash when you feed the bin will help reduce the acidity, and keep the bin smelling sweet.

4. Avoid large quantities of processed and/or acidic food

Processed food, like bread or pasta, can quickly become acidic as it decomposes. Large amounts of acidic foods such as lemon rinds, onion and fruit skins should also be avoided.

5. Only harvest castings when the bin is full

Castings should only be removed when the hungry bin has become full to the top of the taper.

Signs of a healthy bin

When the bin is operating correctly, you should notice the following: - Very little smell
- Large numbers of worms including juvenile worms in the top layer
- Good quality worm castings and very little uneaten food approximately 30cm (12in) below the top layer
- The liquid draining from the bin should be the colour of strong tea with little or no smell

What are compost worms?

Compost worms are different from common garden worms that live in soil.

Unlike earthworms, compost worms do not make burrows in the soil, but live in the surface layer (the top 30cm or 12in). They have evolved to eat rotting plant matter on the forest floor, and are perfectly suited to break down organic waste. Compost worms are generally smaller than earthworms.

Our compost worms are a dual species of Red Wiggler Worms (Eisenia fetida) and European Red Worms (Eisenia hortensis).

Help, my bin's starting to smell ...

If your hungry bin is starting to smell, or the food is rotting before the worms can eat it, add a fine layer of fibrous brown material each time you feed the worms to help balance the bin. You can also sprinkle a fine layer of soil or potting mix into the bin to help balance it. A diet of food scraps can be too rich for the worms unless the scraps already contain plenty of fibre (lots of vegetable stalks for example), in which case you won’t have to add as much to keep your worms healthy and your bin smelling sweet.

The food in the hungry bin needs to have the right ratio of carbon to nitrogen for the bin to be most effective. The ideal carbon to nitrogen ratio for a worm farm is 20:1, however, food scraps can often have a ratio of 12:1. To balance the ratio of carbon to nitrogen, some extra material high in carbon may need to be added to the bin.

Fibrous materials are carbon rich, which also help balance the higher level of nitrogen in food scraps. Also referred to as bulk or roughage – fibre doesn’t tend to break down and rot as quickly as food scraps. It includes paper or cardboard, dead leaves, sawdust or wood shavings, vegetable stalks, old grass clippings (brown).

The bin may also develop an unpleasant smell if it has become too acidic. Sprinkle a small amount of dolomite lime or rock dust on the top layer to help reduce the acidity of the bin. Adding fibre to the food when you are putting it in the bin may also help reduce problems with acidity.

Should I add water?

Generally you should not need to add water to the hungry bin. Food scraps have a high water content, which helps keep the bin moist. The design lets excess water drain from the bin, but ensures enough moisture is retained to maintain optimal conditions. The worms do need to be moist though, so if the bin has dried out, sprinkle a little water on the top of the bin. If you have added dry matter like shredded paper you may also need to add water. Take care not to drown the worms, the top should only be as wet as a wrung-out sponge.

How much liquid should my bin produce?

The bin will produce about half a litre (one pint) of liquid a day when it has a full worm population and is fed regularly. It is important that the liquid is free to drain from the bin at all times.

If liquid from your bin is not collecting in the drip tray, it may be too dry. See Should I add water? above. The filter tray may also have become blocked with paper or plastic if this has been placed in the bin. Remove the floor and check the filter.

Check that the bin is not exposed to intense sun for long periods and move to a shadier spot if necessary.

The liquid fertiliser should be mixed 1 part with 10 parts water before being sprinkled onto the soil around plants.

Juice is evaporating?

If you are not getting much liquid it may be evaporating before you get a chance to use it. In this case you can place a suitable jug or bottle under the floor to catch the juice. Placing a funnel in the neck of a bottle will help catch the juice.

No Juice?

If you have started you hungry bin with commercial compost mix or potting mix, it can take a while for the compost to become fully saturated, and the liquid to start running from the hungry bin. You can help the process along by sprinkling a little water from a watering can slowly over a couple of days until there is juice draining from the hungry bin.

My worms are trying to escape …

Sometimes worms will cluster at the top of the bin, and on the underside of the lid, if it is about to rain. This is a natural response to prevent them from drowning in the wild, or to migrate to fresh food when the ground is wet. They will return down into the surface layer when the rain has passed.

If the conditions in the bin are unfavourable the worms will also try to migrate. This is usually caused by overfeeding, or if the food has become too acidic. However, if you keep the lid on as recommended, it is almost impossible for them to escape. Occasionally a worm may fall from the bin into the drip tray, especially if castings have recently been removed.

If the food is too wet the worms will look fat and pale. Add some dry leaves or shredded paper. Gently use a fork to turn the top layer and create some drain holes on the surface.

If heavy rain is flooding your bin try moving it to a more sheltered location.

Going on holiday?

The hungry bin can be left for two to four weeks without fresh food. Adding shredded paper, dead leaves or dry lawn clippings to the food for a week or two before you go away helps the food last longer. Water any dry material you add to your hungry bin to ensure the bin doesn't dry out while you are away.

If you are going away for a month or two, it’s no problem either. All you need to do is alternate layers of leaves, dried grass clippings, shredded paper with alternate layers of food scraps. A total of 30 cm will last for a couple of months without too many problems. If you are away for longer, you may need to ask a freind to feed your farm while you are away.

Flies, ants and other insects

The hungry bin is designed to prevent pests from entering. However, it is a living ecosystem and some small beneficial insects can exist in the bin quite happily. Sometimes these other insects are eating food the worms don't like or prefer not to eat. Insects may also be present in food scraps that are introduced to the bin, e.g. fruit fly larvae.

The food in the bin will naturally attract other creatures. Sometimes insects like white fly are attracted to the bin because the food is too acidic. Try balancing the food with a little lime, shredded paper, dead leaves or sawdust. Covering the food with a hessian sack, old carpet or damp newspaper will also discourage unwelcome visitors.


If the farm is too dry, ants can also establish their nests in the hungry bin itself. Keeping the surface moist will help discourage ants. Ants can be discouraged from enetering the bin by ensuring the bin is not touching a surface the ants can enter the bin from, and then smearing a layer of petroleum jelly on the legs just under the sockets on the lower body.

Fruit flies

Fruit flies are attracted to rotting fruit or sweet smelling scraps in the bin. Fruit flies will normally be present in the bin, but if you have large numbers it can be unpleasant and indicate that the balance in the hungry bin has changed.

Try burying your food scraps under the top layer. In addition, you can place a couple of layers of damp newspaper flat over the surface. Each of these helps to keep adult fruit flies from accessing the buried food, where they lay their eggs.


Maggots are the larvae of flies. There are many different kinds. The type you may see in your bin will depend on what you are feeding your worms, where you live and the time of year. While many people find maggots unpleasant, they will not harm you or your worms. In fact, they are good decomposers and, like the compost worms, will produce a high-quality casting.

If you haven't added animal proteins, and don't have any foul odours in the bin, then it is likely the maggots you are seeing will be black soldier fly larvae. Once your bin has black soldier flies present, it can be difficult to get rid of them. It may be best to simply allow them to grow out of the larval stage (which they do quickly) and fly off. If you have large numbers present, harvest the worms and get rid of all your affected castings (put them in an outdoor compost pile, or bury them in the garden). Then put your worms back into fresh bedding.


Also known as pill bugs, sow bugs and woodlice. They are beneficial bugs in your bin helping to break down all the compostable material. If you wish to remove them, you could lay damp newspaper on top of the food scraps overnight, in the morning remove the paper with the slaters attached. If you have chickens, you could feed them the slaters. Slaters can also be an indication that the bin is dry so add some water to reduce their population.

Red spider mites

Red spider mites are very common in worm bins. They are usually present when there is a source of bread and protein. These mites can be a problem if you find your worm population depleting. You can remove them by putting in food overnight that the mites are attracted to (like watermelon rind) then remove the next morning with the mites attached and wash them off. Repeat the process until you are satisfied with the result.

Black soldier fly

See Maggots above.


Also known as pincher bugs, these are harmless creatures in the worm bin. They generally indicate a slightly acidic environment, which can be remedied easily by adding a handful of garden lime.

White worms

Also known as pot worms or grindle worms. They will not harm your worms but can be an indication that the bedding is too acidic. Add a handful of dolomite lime or garden lime.


These little arthropods feed on composting material but are also known to feed on small insects including the odd worm. Best to evict these visitors as you see them. Watch out for their pincers!


These omnivores are attracted to food scraps. Avoid putting in any meat products. They also like dark tight crevices so you could uncover the bin for periods of time, which will make the worms work at lower levels and discourage the cockroaches from taking up residence. However, keeping the lid on in the first place will prevent them entering. To get rid of cockroaches without using baits you could try a 1:1 mixture of baking soda and sugar. Spread it around the outside of the bin.

Fruit flies?

The food scraps you have placed in to your hungry bin are very attractive to a host of other critters, not just worms. Normally this is not a problem, but in the warmer months, fruit flies can be an issue. This is especially true if you are eating a lot of fruit like kiwi fruit or bananas which have high sugar levels. The best way to reduce the fruit flies present in your hungry bin is to ensure that you are adding enough fibre to balance the acidity, and to cover the food with a layer of newspaper or leaves each time you feed your hungry bin. Sprinkling some dolomite lime on the top of the food will also help reduce the acidity that is attracting the fruit flies.

The level in the bin has dropped

If the level in your hungry bin has dropped, don't worry. it's an easy problem to solve. Just add some soil or finished compost each time you feed the hungry bin.