Worm Composting
Organic Waste
Starting the Hungry Bin
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What compost worms like
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How much can I feed?
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Should I add water?
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How much liquid should my Hungry Bin produce?
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When and how do I harvest worm castings?
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Characteristics of a healthy Hungry Bin
What worms like
– and don't like very much
Compost worms prefer a balanced diet. They eat their favourite food first but also appreciate some variety. The smaller the food scraps, the easier the worms to digest and process them. They consume most plant-based kitchen waste, such as fruit or vegetable leftovers. Worms do not favour processed foods containing preservatives.
Larger quantities of processed foods like bread, pasta, and other dough-based items are often colonised by moulds and bacteria faster than worms can consume them. Therefore, they should be adequately mixed with other organic waste. Worms don't like large amounts of meat, fish, dairy products, citrus fruits, or onions.
Compost worms also eat non-woody garden waste and manure. However, only small amounts of garden waste should be added to a Hungry Bin, as fresh grass clippings, for example, can heat the bin and cause issues. Manure from carnivorous animals should be fed to worms in small quantities and should not come from animals treated with anti-worm medications.
If you intend to use worm castings and worm tea for edible garden plants, do not feed the dog or cat faeces to the worms to avoid the potential transmission of intestinal parasites.
What worms like
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Most fruit and vegetable scraps
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Pulp from juicing
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Cooked food
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Tea bags and coffee grounds
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Crushed eggshells
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Torn egg cartons
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Newspaper shreds (moist) and cardboard shreds
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Hair and dust from the vacuum cleaner
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Soiled paper, towels, paper tissues
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Garden trimmings in small amounts, grass, small branches, leaves, sawdust, and wood ash
What worms don't like very much
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Citrus fruits and peels from acidic fruits
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Onion, garlic, leeks, pepper
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Meat, fish, and dairy products
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Bread, pasta, and other heavily processed wheat products
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Fats and oils
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Glossy paper
How much can I feed the worms?
Worms can eat about half their body weight every day. The amount of organic waste you can add to the Hungry Bin daily depends on the worm population size. The Hungry Bin can be inhabited by approximately 3 kilograms of worms. It takes about six to eight months to reach this quantity if you start with 0.5 – 1 kg of worms.
Worms do not need to be fed daily, but the Hungry Bin should always be three-quarters full.
If the Hungry Bin is overfed and this layer becomes too large, some waste may ferment before the worms can eat it. Compost worms no longer like their food when it ferments, becomes too mushy or slimy, and starts to smell. If there is too much fermenting, mushy, or slimy waste, it may help to add a small amount of shredded cardboard to the top layer.
The layer of uneaten waste should be at most 5 cm. If the layer of uneaten waste is deeper than 5 cm, stop feeding until the worms have consumed the existing feed.
You can check this by digging through the top layer and seeing how deep the waste is untouched by the worms. In a healthy Hungry Bin, a mixture of adult and young worms, worm cocoons, and initial worm castings should be visible 5-10 cm below the surface. The mix of large and small worms and worm cocoons is a sign that the conditions for the worms are optimal for reproduction.
About 20 cm below the surface, the waste should have been completely transformed into worm castings. Finished worm castings look like high-quality compost and smell like forest soil.
Occasionally, add fibrous materials such as cardboard, paper, dead leaves, old garden clippings (brown), or garden lime to balance the acidity (PH) in the Hungry Bin. If garden lime is available, you can sprinkle a handful on the surface every week.
In extreme cases, if there is a lot of fermenting food scraps in the Hungry Bin, the food may need to be removed entirely and restarted.
Generally, it is better to underfeed the worms than to overfeed them.
Feed a small amount daily and ensure the unconsumed waste does not accumulate. Distribute the waste over the top layer of the Hungry Bin.
The smaller and softer the waste, the easier it is for worms to eat. However, the waste should not be too mushy to allow the worms to breathe (worms breathe through their skin). Gradually increase the amount you feed the worms as the worm population grows. Worms regulate their reproduction based on the amount of food available.
You can add a maximum of a 2.5 cm high layer of organic waste to the Hungry Bin daily.
Be careful not to overfeed the worms!
This is rarely necessary. Organic waste typically has a high water content, which keeps the Hungry Bin moist. The Hungry Bin system allows excess liquid (worm tea) to flow out of the Hungry Bin as plant fertiliser while retaining enough moisture inside to maintain optimal conditions: damp but not wet. If the Hungry Bin does dry out, you can sprinkle some water inside.
The worms may need some water if you have added dry materials such as paper scraps or cardboard. It's best to moisten cardboard and paper always. Please be careful not to drown the worms. The surface should not be wetter than a squeezed sponge.
If you do not regularly harvest the worm tea, there is a possibility that it may evaporate before you have the chance to use it.
Should I add water?
The Hungry Bin produces approximately half a litre of worm tea (leachate) daily with a maximum worm population and regular feeding. It is essential that the worm tea can flow into the drip tray at all times.
If the worm tea is not collecting in the drip tray, the contents of the Hungry Bin may be too dry. (See above 'Should I add water?'). The filter may be clogged for example by plastic if this has been placed in the Hungry Bin accidentally. Remove the bottom of the Hungry Bin and check the filter. Also, ensure that the Hungry Bin is not exposed to intense sunlight for an extended period. If necessary, move the Hungry Bin to a shadier location.
The worm tea is a liquid fertiliser and should be diluted with water (1 part worm tea to 10 parts of water) before spraying it on the soil around plants or on the plants.
How much Worm TEA should the Hungry Bin produce?
When and how to harvest worm castings?
To ensure that the finished worm castings are mature and compact, it's advisable to harvest the worm castings only when the Hungry Bin is full to the top.
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When removing the base, the conical shape of the Hungry Bins ensures that only the lower part, i.e., the worm castings, falls out. If the worm castings are compact and have had enough time to mature, they should be mostly free of worms and stick together, making it easy to extract the worm castings. Harvesting the worm castings before the Hungry Bin is full may negatively impact its efficiency. If the base is removed before the worm castings are compacted, more of the non-mature contents of the Hungry Bin, including worms, may fall out.
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It may take up to 8 weeks or longer for the first batch of worm castings to be sufficiently finished for harvesting. This depends how many worms are living in your Hungry Bin.
In the worm castings, there may still be worms present. These worms can be easily separated from the worm castings by spreading the castings on the lid removed and inverted from the Hungry Bin. The worms remaining in the castings will then migrate to the light-protected lower layers; the top layer can be lifted off the lid and used as a tray for planting. The remaining layer with worms can be tipped back into the Hungry Bin.
Worm castings and worm tea can be used just like compost. For example, you can heap the worm castings around plants or spray the soil with diluted worm tea. Pure worm castings can burn the roots of small plants if not diluted. For smaller plants, mixing the worm castings first with regular soil is advisable. Worm castings are pH-neutral and can be used safely for most plants. Even a small amount of worm castings or worm tea can enhance the performance and health of plants.
Characteristics of a Healthy Hungry Bin
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​The Hungry Bin has almost no odour.
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Close to the surface, many worms are visible – including young worms.
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30 cm below the surface, no more waste can be found, only high-quality worm castings.
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The worm tea from the Hungry Bin should have a brownish cloudy colour and little to no smell.
Download the Hungry Bin
Owners Manual