I’ve long believed that worm farming is one of the best ways to grow stronger, healthier plants in containers. When I first started growing food on a small balcony in London, a wormery also transformed how I viewed food waste. Banana skins, tea bags and vegetable peelings stopped being rubbish and became a valuable resource that could be turned into rich compost and healthy plants.
In this episode, I speak with Anna de la Vega, founder of the Urban Worm, who has spent more than a decade helping people across the UK set up wormeries in homes, schools, workplaces and community projects. Together we explore everything from getting started with worms to the role they could play in tackling waste, improving soils and building more sustainable communities.
Listen here on Substack, or on Spotify or YouTube.
Some of the things we discuss
Start small and keep it simple
One of Anna's strongest messages is that worm farming doesn’t need to be complicated or expensive. A few buckets, a storage box or even an old recycling bin can work perfectly well.
Worm farming is animal husbandry—and the secret is learning how to keep the worms happy. Their key needs are simple: organic kitchen waste, carbon (cardboard or woodchip), moisture, ventilation, drainage, and protection from direct sunlight.
Choosing the right wormery
Anna is not particularly enthusiastic about some of the more expensive commercial wormeries available today and often prefers simple DIY systems. Many of the stacking wormeries on the market are also heavy and the worms can be slow to migrate between layers.
For larger-scale or family use, more surface area increases the amount of food waste the worms can process - and makes them more forgiving and easier to look after. A larger surface area also allows worms to move away from disliked food and adjust to new diets. Good examples include old baths, large storage boxes, and old recycling bins.
The secret is balance
Many wormery failures happen because people give worms too much of one thing. Anna shared how she once killed a colony by feeding them too many apples, while others overload wormeries with coffee grounds. Worms thrive on a varied diet and a balance of food scraps and carbon-rich materials such as cardboard.
We also discuss how worms can adapt to a surprisingly wide range of food sources. Anna explains that worms raised on one type of feed may initially be reluctant to tackle a very different diet, but over time they adjust. This helps explain why newly purchased worms can sometimes seem slow to process our kitchen scraps and why introducing new foods gradually often works best.
Worms don’t actually eat your food waste
One fascinating insight is that worms are not directly munching their way through vegetable scraps. Instead, they are feeding on the microbes that break down the waste. Chopping food into smaller pieces helps create more surface area for those microbes and speeds up the process.
Carbon matters more than many people realise
Anna has tested the biology of her compost and discovered that many wormeries are too bacteria-dominated because people don’t add enough carbon. Cardboard, egg cartons and woodchip all help create a healthier balance and support fungal life in the compost.
We also explore the value of woodchip as a carbon source. As well as helping balance food-rich wormeries, woodchip improves structure and airflow in both the wormery and the finished compost. Anna uses it extensively in her commercial systems, while I’ve found it particularly useful for improving the texture of worm compost and creating a more fungal-rich growing medium.
Horse manure is worm gold
If you have access to horse manure, Anna describes it as one of the best things you can add to a wormery. It encourages worm breeding, and helps restore struggling systems.
Be cautious about “worm wee”
Many commercial wormeries are marketed around the liquid that drains from them. Anna explains that this liquid is technically leachate rather than true worm tea, and its quality can vary considerably. Leachate can contain harmful bacteria and is not recommended for large-scale or edible crops.
Instead, Anna recommends making a simple worm compost tea. This can be as easy as steeping a handful of finished worm compost in dechlorinated water and using the resulting liquid as a soil drench or foliar feed. It's an inexpensive way to spread the biology and nutrients from a small amount of worm compost much more widely around the garden.
Worm farming is about more than compost
Throughout our conversation, we keep returning to a bigger idea: worm farming changes how we think about waste. Nature produces no waste, and wormeries allow us to mimic the natural recycling systems found in woodlands and healthy soils. They help keep organic matter out of waste streams, reduce transport, create valuable compost and reconnect us with natural cycles.
Why aren’t worms more popular?
One of the most interesting parts of the discussion is hearing how mainstream worm farming is in other parts of the world. Anna describes seeing worm composting used in prisons, schools, farms and municipalities in the United States, Cuba and the Philippines. In some regions of the Philippines, worm farming is even built into organic certification schemes.
As Anna points out, worm farming may not attract much attention because it is such a simple, low-tech solution. But perhaps that’s exactly why it deserves more attention.
I hope you enjoy the conversation.
Links and more information
The Urban Worm - Anna’s website has lots of useful information and resources -subscribe to her monthly newsletter on this page.
Ted Talk - Nick H, aka the ‘Worm Dude’, from the Monroe Correctional Complex in the USA describes the prisoners experience of worm farming.
How to make a wormery - my guide to making a simple wormery, and a basic feeding guide.
Ecothrive - for soil testing and chlorine removing solution.
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