Most frequently asked questions

Here are the most frequently asked questions we've received at Subpod.

Subpod is an in-ground worm farm, the first ever of its kind! Above ground compost systems are often difficult to maintain and attract pests. Worm farms that are above ground also fail when they get too hot or cold – but not Subpod. Subpod sits 90% below the soil level in your garden, so the compost worms that live inside can come and go freely (nourishing the soil directly). The soil insulates your compost and protects your worms from harsh weather, so you can keep composting no matter the season!

We designed Subpod to deal with all the common issues associated with traditional compost systems:

- It’s aerobic, using odourless microbes to speed up the composting process

- The ventilation panels keep it smell-free with fresh air

- It’s pest-proof and lockable (great if you deal with raccoons)

- It doubles as a garden seat, subtly hidden amongst your plants

Want to know more about what makes Subpod different? Check out our design page!

Yes! Being underground is what makes Subpod different from other compost systems. The soil provides insulation and a way for worms and microbes to explore your garden and feed your plants. Above ground compost systems struggle to keep worms and microbes comfortable, and even alive, in summer and winter – but underground they're safe and happy (which is the secret to good compost).

You can compost a much bigger variety of materials in Subpod than in other worm farm systems! See the full list below:

FOOD WASTE
Most food waste can be composted in Subpod without worry. Fruit and vegetable scraps, eggshells (crush them first), coffee grounds, used tea leaves, spoiled plant-based milks, grains, pastas, breads, nuts (and their shells), seeds, pits, husks and so on. Small amounts of meat, seafood, dairy foods, citrus, onion and garlic may also be added. Subpod can also process spicy herbs, peppers and oils but it’s best to introduce these slowly in small amounts at first, and only once your worms are fully established (after around three months).

PAPER & CARD
Most scrap paper and cardboard can be added to Subpod, as long as it’s not laminated or super glossy. Again, the smaller the pieces, the better. Junk mail, office paper, bills, envelopes (no plastic windows), post-it notes. Paper plates, tissues, egg cartons, paper cupcake liners, baking paper, even card and paper packaging is fine.

NATURAL FIBRES
Cotton wool balls and pads, tampons, toilet paper cores and even natural latex condoms and gloves can go into Subpod. Old clothing, face washers, napkins, tablecloths and very old towels can be used as long as they are made from natural fibres like cotton, tencel, linen, hemp or wool (no polyester, nylon, acrylic or blends) – just shred them into small pieces first. Washer and dryer lint is okay too, as long as it comes only from clothing made from natural fibres.

WOOD AND BAMBOO
Sawdust (no paint) is great. Toothpicks, disposable wood, bamboo and bioplastic cutlery and crockery can be composted, along with dead matches, bamboo skewers, garden prunings (cut 'em up small), and charcoal from the fireplace – as long as you wash off the ash which is too alkaline for Subpod.

HUMAN AND ANIMAL WASTE
Human hair and nail trimmings, used facial tissue, used cotton bandages and sanitary items can all be composted in Subpod, as long as they are made from 100% natural fibres. Pet hair of all kinds is fine, along with soiled newspaper and hay cage liners and faeces from vegetarian pets and livestock (rabbits, guinea pigs, hamsters, cows and horses). Dog and cat faeces are NOT suitable for Subpod if you’re eating the plants growing around it. But fine if you want to have a separate one for this purpose.

NOT COMPOSTABLE
You cannot compost non-organics such as plastic, tin cans, cigarettes, building waste, toxic waste, glass, or any other similar materials in Subpod.

One fully functioning Subpod can compost 15kg (30lbs) of food waste a week! The average family generates roughly 7.2kg of food waste a week, so Subpod can handle about double the waste your family should need it to.

It can take 1 - 3 months for the worm population inside your Subpod to build enough for it to compost at peak levels. It’s also possible to optimise your Subpod to compost even more waste by incorporating biochar into your system – but that's a little advanced.

An average household can compost all their food waste with 1 Subpod! If there are 8+ people in your home, you may want a second Subpod.

The average family generates 7kg (15lbs) of food waste a week. An established Subpod can compost 15kg (30lbs) of food waste a week – two families worth of waste! It takes 1 - 3 months for your Subpod to reach this capacity. Compost worms balance their population against the amount of food waste you feed them though, so you can still compost with Subpod even if you’re a household of one.

To harvest your compost, just stop feeding one side of your Subpod and only feeding the other compost bay. Your worms will naturally migrate to the other side after around 2 weeks – leaving you a full bay of rich compost ready to be scooped out and spread through the garden!

You can also use the 'Sunlight Method'. To do this, scoop out your compost, worms and all, and pile it onto a tarp. If you let this sit in bright sunlight for 5 minutes, the worms will move to the bottom center of the pile and you can collect the worm-free castings! Once you're done, just return the worms left to your Subpod.

Yes! But you may need to do a little tweaking. Subpod relies on the worms and microbes to compost and they can go dormant if they get too cold.

Subpod is naturally insulated by the surrounding soil so during winter the temperatures inside will be higher than any above ground compost system. But things will slow down if the temperature drops below 55 F (12C). We’ve found 3 proven methods that keep your worms warm and happy over winter.

Yes! Subpod is a vermi-composting system, which means it relies on compost worms to break down your food waste. Without compost worms, Subpod can't do its job.

We recommend buying worms for your Subpod locally if possible, but you can also find them online. If you need more information on how to buy worms, read this blog!

Unfortunately, no. But we do have a few tips though!

- Try to purchase worms locally. Worms always seem to be happier if they don’t have to be shipped for miles across the country.

- Get a diversity of worms. There are 3 main types: Red Wigglers, Night Crawlers and Tigers. Each is better suited to different environments and
temperatures, so it’s helpful to get all 3.

- Jump on to our growhub community and see if there’s a local Subpodder that will give you some worms. Make a friend and score some worms at the same time!

It’s best to start your Subpod with about 2,000 worms. It is possible to start with only 1,000 but you’ll have to give your worms a little extra time and TLC while they build up their population.

Here’s a video showing you from start to finish how to get your worms ready.


Nope! Just pick the bed you want to boost growth in the most. Subpod feeds the garden bed as the worms and microbes explore the soil, fertilising your plants at the root level. Once you’ve generated some compost you can spread it around your other garden beds and they’ll get to enjoy the benefits of Subpod too.

Subpod is made from Polypropylene (P.P.) which is a type of plastic. As an eco-conscious company this might seem like an odd choice, but it’s the most sustainable option available right now.

We experimented with steel and bioplastic Subpod prototypes, but they all deteriorated way too quickly. It would have been unethical to sell a product with only a 1 - 2 year lifespan, and bad for the planet to constantly ship new replacements.

We strongly oppose toxic & single use plastics – which is why we chose Polypropylene. It’s durable, capable of withstanding a wide range of temperatures, naturally BPA free and food + water safe. If you look up your fridge’s materials, it’s likely that P.P. is helping to keep your veggies cool!

We’re very excited for the future of bioplastics and other biomaterials, and we can’t wait until there’s an even more sustainable option for us to make Subpod with.

Can't find the answer you were looking for?

Customer Support
Having questions is understandable, especially if you're new to composting. We've tried to answer the most frequently asked questions about Subpod below – if you can't find your answer, please don't hesitate to submit a ticket to our customer service team by clicking the link below.
Submit a support ticket

Join the Community
Alternatively, join our thriving community of compost and gardening enthusiasts. Ask questions, meet like minded people and explore.
Join the Grow Hub