Subpod® FAQs

Why Choose a Subpod?

Subpod is a unique invention which combines worms and composting underground. The Subpod has a series of holes throughout the box which allow the worms to move freely in and out. This means the surrounding soil is aerated and nutrients are delivered directly to the roots of the plants where they are needed most. 

The Subpod has been rigorously tested over the past 8+ years to allow for maximum efficiency of allowing worms to move freely in and out, while keeping unwanted pests out. At the top of the Subpod is a special mesh which allows air to flow in and out while being strong enough to keep out large critters such as rats, possums, and anything else living in your garden.  

The Subpod Airflow Panel is a key design factor in the Subpod. It means that the compost is aerated easily which creates anaerobic/oxygen rich environment and no smelly compost heaps! 

Worm mobility is key for this product and is really what makes Subpod more advantageous over conventional systems. If something is added to the Subpod which the worms do not like, e.g. onions or chilies, the worms can move to the other side of the Subpod, or move out into the surrounding soil and move back into the Subpod when they like.

Subpod is an underground system, which means more stable temperatures all year-round. Most worm farms are exposed to the elements and can easily die with temperature fluctuations.

The Subpod is made from water and food safe plastic which has a minimum life of 10 years in the soil without any leaching or degradation.  

Another unique factor that makes the Subpod special is its unique interconnecting design that allows multiple modules to be added for larger volumes of waste. The modular design, along with the bench seating aspect, makes it perfect for cafes and restaurants, as well as individual family gardens. The Subpod can be buried into the ground, or made into an above-ground garden bed which you can sit on and enjoy.

The idea is mimicking nature where worms eat, roam, and spread nutrients. Worms are not confined to the Subpod, and they learn to return to the Subpod for feeding.  As for getting full, it does not fill up as quickly as most systems because of the worm mobility, plus the worms and microbes are continuously eating.  This keeps the compost levels low inside the Subpod. We find that you end up only needing to empty the contents a couple of times per year, or more if you would like to distribute your compost and worm castings throughout your garden.

In most systems, because you are creating worm castings in a confined area, you need to take them out and apply them to your garden. This is a two-step process. For Subpod, it is just the one step of composting and the soil biology does the rest!  Of course, there are times when people will want to use worm castings in other areas of their garden, and we have designed the Subpod lid to allow for easy access to scoop out your worm castings.

You can purchase from local worm suppliers. Generally, compost worms can be bought from community gardens, nurseries, worm farmers, or home hardware stores. There are also worm suppliers online.

It is safe for worms to be mailed. They're typically fine in transit for 4 to 5 days with no hardship.

Tiger worms or Red worm (Eisenia foetida) and the Indian blue worm (Perionyx excqvatus) are the best worms for Subpod.

You CANNOT use worms from your garden; these are earthworms and have different taste buds than compost worms. Compost worms have evolved to eat rotting plant matter.

Bad smells indicate that the composting process is out of balance. To make composting appealing for people, the Subpod was designed with this in mind to avoid this problem.


Compost that is rich in oxygen does not smell. This is because the organisms that thrive in an oxygen-rich environment do not produce smelly by-products. Oxygen-loving microbes will break down the food into non-smelling smaller components. This type of composting is called aerobic composting.

One of the key design principles of the Subpod was to allow a large airflow into the composting system to encourage aerobic composting.

Another magic component of the Subpod is its use of worms! Worms break down the food scraps into smaller particles quickly, and the worm's intestines also have good bacteria inside them as well.

As the worms break down the food scraps they excrete the smaller particles into the soil around them with the good bacteria/beneficial organisms. These are the non-smelly organisms wanted in the compost breaking down scraps. The microorganisms then get into breaking down the particles to even smaller components (which do not smell).


The Subpod comes with some specific instructions to make sure you get the right ratio of wet, high nitrogen food to dry, carbon-containing waste. This will keep the system balanced and not smelly.
To achieve this in a Subpod, merely ensure that you add some dry carbon material when you put your
wet food waste into a Subpod. Dry carbon waste are things like newspaper and cardboard. Wet, high nutrient foods are things like lettuce and apples. A detailed instruction manual is included with every Subpod.


Using the worm aerator or mixing by hand every time food is added to the Subpod ensures that the food is mixed through the Subpod and broken down faster as well as oxygenating the system so it does not become smelly.


Another factor to keep away smells is to make sure you don’t overfeed your worms. At the start when your worm population is building up, you will add your kitchen scraps at a smaller rate. When your Subpod is up and running you will be able to add 30 liters/15 kilograms of waste per week into your Subpod.

The Subpod is designed with large airflow panels around the top of the Subpod. These areas allow airflow in the above-ground region of the chamber to maximize aerobic activity.


When new food waste is added and mixed in using the worm aerator, this brings the air (and importantly oxygen) down to the worms and bedding keeping the system from getting anaerobic and smelly. Also, dry carbon-rich material is added when the food scraps are put into the system, this keeps the system from getting overly wet, and further maintains the pro aerobic conditions of the environment to minimize the generation of bad smells/anaerobic activity.

Once your Subpod is fully up and running and you are adding 15 kg / 33 lbs. of organic waste per week, after 1 year (52 weeks), you have composted 780 kg / 1719 lbs. of food waste! In a landfill, that food would have generated a lot of methane which is at least 25 times more potent a greenhouse gas than CO2. Using the conversion factor used by the United States EPA to estimate the waste carbon emissions in CO2 equivalents when waste is diverted from landfill, this gives a value of approximately 2.24 metric ton equivalents of CO2.


Considering the average car passenger driven 11,500 miles/ 18,500 km per year produces 4.7 metric tons of carbon dioxide equivalents, you are keeping almost ½ a years worth of a car’s carbon emissions out of the air for every Subpod composting food waste!


Subpod’s pilot project at Habitat Byron Bay has 10 active Subpods in 2 raised garden beds. When fully utilized, these are composting 15 kg of organic waste per Supod x 10 Subpods x 52 weeks in a year = 7800 kg of waste composted. This accounts for the higher potency of methane as a GHG, and expresses the total amount as 26.6 metric tons of carbon dioxide ( CO2 ) equivalents kept out of the atmosphere. This is equivalent to the CO2 emissions from more than 5 passenger cars each with an average annual driving distance of 11,500 miles/ 18,500 km.

With Subpods aspirational vision of 20,000 people using Subpods, diverting this much organic waste from landfills will reduce toxic greenhouse gas emissions by 53,300 metric tons of CO2 equivalents per year. This is equivalent to a year's worth of carbon emissions from 11,340 cars.


Harvesting this compost and adding it to the soil to feed your plants, you are both increasing soil carbon and providing plants with the nutrients and microbes that support photosynthesis to pull additional CO2 from the air as the plants grow.


When plants grown in this soil are themselves eventually composted, this cycle continues to add to soil carbon. Because most of our soils have become depleted of carbon, there is a lot of capacity for soil to absorb more carbon.

Dimensions and Specifications

When designing the Subpod, many factors were taken into consideration. The design team found that the best material to use now for the Subpod is polypropylene which is naturally BPA free. Polypropylene is one of the safest plastics available from a health perspective with no endocrine disruptor chemicals and undetectable leaching. Because the Subpod is designed for durability and long life use, as a priority, initially started making Subpods from virgin polypropylene. There is ongoing field testing of blends of up to 50% recycled polypropylene to verify these blends have sufficient strength and longevity to permit the use of a percentage of recycled polypropylene in Subpod manufacturing.

Polypropylene is water and food safe and has been used in the food industry for many years, it is able to withstand high temperatures of about 110 degrees Celsius/ 230 Fahrenheit. Using polypropylene, Subpods are expected to have a minimum usable lifespan of 10-15 years in the soil without any leaching or degradation which is important since the Subpod will contain and be surrounded by a microbe-dense soil in a wide range of conditions, including dampness and high humidity.

Doubling as bench seating requires that the materials chosen support body weight. Polypropylene based Subpods can bear up to approximately 200 kilograms/ 440 pounds.

Finally, the Subpod can be recycled when it reaches the end of its life in your garden, completing its life cycle. There are exciting plastic substitutes being developed which are continually up for consideration, but most of these are designed to be composted after use and currently the need is for the Subpod to hold up strong for many years while it is efficiently composting all of your kitchen waste. It’s number for recycling is 5.

The Subpod Grow Garden Bed is strong and stylish, made from high-quality steel with an anti-corrosion coating of aluminum and zinc for long life. The expected life of this type of steel is at least 15 years. It is 4 times stronger than galvanized steel.


The bolts and screws are made from stainless steel which will also have a long life.

We have not had the zinc aluminum coating of the steel Grow Bed evaluated by a lab to certify that it is free of lead. You may certainly use the Subpod with a wooden garden bed, or perhaps you can find a local steel garden bed that has been lab certified to be free of lead as a second option.

Dimensions: 120cm L x 90cm W x 45cm H / 47.2” L x 35.4” W x 17.7” H

Each worm blanket is 36cm/14 inches x 42cm/16.5 inches.

There is one worm blanket for each side of the divider included with your Subpod purchase.

Subpod is fine to use for 1 person and under 15 kilograms per week. You will start with about 2,000 worms and they will gradually build in numbers based on their environment. If you don't feed them much, they will eat what they have, and not make more babies. You may also consider scrap sharing with neighbors, friends and family. Ask them to donate food scraps to you Subpod. This stops waste from going to the landfill (creating methane gas), and creates more compost for you and your garden!

We believe it's highly unlikely bears will be attracted to the system, as Subpod is virtually odorless. Subpod also has the option of a lock system so you can padlock it preventing clever animals from lifting open the lid. Subpod's lid is also, extremely strong and durable since it has the capacity to hold 440 pounds of weight!

In saying all this, as you're well aware, bears are powerful creatures and if they are hungry or curious they can break into anything!

Subpods are designed to be used for a family of up to 4 people. The capacity of the Subpods once they are up and running will be 30 liters/15 kilograms or approximately 33 pounds of organic waste per week.


At the beginning as you are getting your Subpod up and running, you will not be able to put that much waste in your Subpod.

You will need to let your new worms settle into their new home and build up their numbers before they will be able to eat 15 kilograms / 33 lbs of fruits and veggies a week.


Worms are also adaptable, so if your organic waste is reduced for whatever reason, they will adapt to their environment. They will also not be confined to the Subpod, but will be free to move throughout the garden bed and come back to the Subpod for their dinner.


If you eat a lot of fruits and vegetables and have more organic waste than 30 liters/15 kilograms per week, then you can purchase 2 or more Subpods. The Subpods can fit together due to their modular system and be used as a bench seat in the garden, or can be installed in separate garden beds.

Setup and Maintenance

There are some simple steps to follow when your Subpod first arrives. Click the links below to download the instructions!

How to Feed your Subpod

3 Ways to Keep your Subpod Happy

How Much can I Feed Subpod

What Can I Feed Subpod

When you add your food scraps to Subpod you will need to mix them through using an aerator. This takes a few minutes per week. Using the aerator helps to mix the food through the Subpod so that the worms and microbes can break them down more easily, as well as oxygenating the Subpod. Oxygenating the Subpod means an aerobic environment, and reduction in smells.

The airflow panels need to be kept clear from plant growth growing up against the Subpod. You will need to pull away plants occasionally.
If the soil surrounding the Subpod settles and starts to reveal the Subpod worm holes exposed to the air (beneath the airflow panels), more soil will need to be added to cover the holes.

Otherwise, just keep feeding your worms and keeping the worm blanket moist when you are adding more food.

It's important to have carbon (dry material) in any composting system. Although Subpod is a little more relaxed with this rule because the worms and microbes can take carbon from the surrounding soil.

We still suggest placing a handful of carbon every time you feed. A good basic ratio is 2 parts food waste to 1 part dry material such as sawdust, cardboard, or paper. If you have wetter food waste you may need to add a bit more dry material.

You do not need to add extra water to the Subpod, as there should be plenty of liquid coming from your food scraps. It's important to make sure the worm blanket is kept moist though.

To test if the worm blanket has enough moisture… Squeeze the blanket. Only a few drops should come out.

If no water drips out you will need to soak the blanket in a bucket of water

Some people have actually found that they don’t need to water their garden as much due to the moisture coming from the food scraps.

It will take around 17 to 22 weeks to convert organic waste to compost (for a full Subpod).

So, you could create compost for your other garden beds every 4-6 months. You can also plumb your Subpod to gain access to the worm juice, which is full of microbes and nutrients and spread this around to your garden beds.

Lastly, If you would rather take the compost out of your Subpod sooner, you can simply use the internal divider wall in Subpod at any time. This allows you to stop feeding one section so the worms can migrate across to the other side. You can then scoop out your finished compost after 2 weeks - worm free- and begin the process again :)

A pitchfork will work, however, the tines of the pitchfork will most likely scrape the plastic walls and floor of the Subpod, accelerating wear as the bedding is being turned.


We recommend that you use the Subpod Compost Aerator instead which is made from 303 stainless steel. The single point on the aerator is designed to avoid gouging the bottom and sides of the Subpod as the contents are being mixed. It is corrosion resistant and should last as long as the Subpod. The handle is made of safe, durable and recyclable plastic.

If the Subpod is in a raised garden bed, the immediate area (half a foot or 15cm) around the Subpod will be enriched quickly (within several months). Once the Subpod is full (after about 6 months depending on feeding and worms), by sprinkling the castings through the bed, you will enrich the entire bed. The larger the bed the more gradual the process for the entire bed to be enriched.

For a single Subpod, this works well for a raised garden bed of up to 3 feet by 5 feet or 90 cm by 150 cm. For larger beds with a single Subpod, the best approach is to sprinkle castings around individual plants in the bed when emptying the full Subpod of castings.

Learn more from Subpod®

Click here to learn more from the experts at Subpod®! You can also give us a call at (877) 696-8889 with any questions.