Worm power: turning kitchen waste into compost gold


Variety being the spice of life, mix up what you feed your worms

A compost pile in a second-floor flat may not be a practical solution to dealing with your food waste, but if you don't have a garden, a homemade wormery might just be the ticket
For the first few days of having worms I felt like a new mother, constantly peering in to check on the welfare of my little ones

When the fishing tackle shop you've gone to in search of worms is right next-door to a funeral parlour, you know you've hit vermicular pay-dirt.

Packed to the rafters with lines, reels and rods, it was from this unassuming angler's paradise that I liberated the 50 or so dendrobaenas - the artists formerly known as 'bait' - that would become the bedrock of my first home-composting enterprise. Together we were going to build an empire. I just hoped they hadn't been dug up from a graveyard.

The idea for a wormery came to me as I scraped a pile of potato peelings into our makeshift food bin. Our council bin had disappeared a few months ago, and fruit flies had taken to circling like vultures the growing heap of scraps in an open box beside the sink. Something had to be done.

Living in a gardenless second-floor flat in London, it hadn't occurred to me that composting could be an option. With a raft of wilting house plants crying out for attention, however, and news of environment minister Hilary Benn's proposal that households be fined for binning food - almost seven million tonnes of it goes to landfill annually - worms seemed the obvious low-tech, low-maintenance solution.

Nature's ultimate recyclers, these amazing creatures consume waste and excrete a nutritious vermicompost that vegetables and plants love. There are a multitude of wormeries available to buy, but as their homes are as simply constructed as the houseguests, I decided to try creating my own.


I chose a 35-litre plastic storage container for my wormery - try Freecycling for one if you don't have one lying around - but they can be any size. Worms don't like the light, so make sure it's made of dark plastic and has a lid for easy access and to keep out fruit flies. If it's air-tight, drill a series of holes 5cm from the top and bottom, ensuring the drill bit diameter is smaller than that of your worms to avoid escapees. Drill a few holes in the bottom to collect any liquid; diluted, it makes great plant feed. Worms breathe through their skin so they like it moist, but you don't want them drowning.


Worms need to have somewhere to burrow. You can use a variety of things for this: peat moss, well-rotted manure, leaf mould, newspaper or cardboard. I used old newspaper. Tear into long strips along the grain, enough to fill your container, then take a quarter and dunk into water, squeezing out until what's left is the consistency of a wrung-out sponge. Place in the bottom of your container, pulling apart to create some structure and allow the air to circulate. The rest of the paper goes back in on top once you've added your worms.


Composting worms are not the same as those you find in soil. They are red worms: dendrobaenas in my case, but tiger or brandling worms are also used; the latter can be harvested from compost or manure piles - just thankfully not from any graveyard. Dendrobaenas are slightly bigger and more robust; they may not reproduce as quickly as tiger worms, but eight can apparently still become 3,000 within a year! Tigers, though smaller, tend to eat more per bodyweight.

For the first few days of having worms I felt like a new mother, constantly peering in to check on the welfare of my little ones

A number of websites deliver worms direct to your door, but be sure they aren't going to be held up in any postal strikes. Worms Direct offer 250g of composting worms for £9.30, The Recycle Works £11 for 250g and Wiggly Wigglers £12.50 for 250g. Sharp's Fishing Tackle in north London, where I got my worms, sells tubs of 25 or so worms for £1.80 (020 7485 1759).

Dendrobaenas are popular with anglers as they're particularly wriggly, making them ideal bait. It's certain mine were going to a better place.
Once their new home was prepared, it was simply a case of watching proudly as they wriggled in to their bedding. I put a little food to one side - banana skins, teabags, the odd loo roll; the smaller you make it, the quicker it's digested - and placed the wormery in our storage cupboard off the communal stairs.

It isn't the warmest place, so I stuck a length of bubble wrap around the outside to provide some insulation. Dendrobaenas can tolerate temperatures from 3-25C, but thrive between 12-18C, when their metabolism - and sex drive - increases.



See also:


Your worms will need a good few weeks to settle in to their home, and it's important not to overfeed them. It may be a slow process to begin with, but as your worms multiply so will their appetite. A worm can eat half its own bodyweight a day and the population will regulate itself depending on how much it's fed.

Variety being the spice of life, mix up what you feed your worms: not too much of one thing. They'll eat practically anything organic, including fruit and veg, coffee grounds and filters, teabags, bread, crackers and cereal, and the odd bit of grass and leaves, though check it's pesticide-free, and not too much as this will cause your wormery to overheat. Avoid too much citrus, tomato or onion, as high acidity can harm your worms. Some shop-bought kits come with a lime mix to neutralise the natural acidity of your wormery, but broken-down eggshells do the same job and provide grit to aid your worms' digestion.

Avoid meat and fish, which will smell, as well as anything diseased. If the wormery smells anyway, it's probably too wet, in which case add more carbon-heavy 'browns' - cardboard, dry leaves, paper, even the contents of your vacuum cleaner. If nothing is happening it's probably too dry, so add nitrogen in the form of 'greens' - vegetable and fruit peelings.

Harvesting your compost

Most shop-bought kits operate a stack system: the lowest tray is filled with worms and food; once only compost is left, food is placed in the tray above and the worms head upwards. You'll tend to notice when it's time to collect vermicompost from your homemade wormery: the bedding will be mostly gone, replaced by dark, soil-like worm castings.

Tip your wormery out onto a large sheet or piece of cardboard and form into a cone shape. The worms will burrow in to avoid the light, so collect the top of the compost cone. Wait a few minutes for the worms to move further down again and repeat. Eventually you'll be left with mostly worms, which you can return to your freshly re-bedded wormery. Egg cocoons, soft yellow pods that darken over time and look like apple pips, should be returned too. Spotting these is good news, as it means your worms are happy enough with their world to be bringing little worms into it.

The journey begins...

For the first few days of having worms I felt like a new mother, constantly peering in to check on the welfare of my little ones. As the days stretched on it became apparent that the worms would be taking things at their own pace and wouldn't be rushed.

Two weeks in I noticed the pieces of stale bread I'd thrown in were covered in blue fluff, and pulled them all out in a panic. Decomposition is a perfectly normal part of the process of decay, however, making the organic matter more edible, so don't be alarmed by any peculiar processes taking place.

One lesson I've learned is that it pays to get a lot of worms - the more you have, the quicker the recycling. So while I wait for my worms to get up to speed, I'll keep taking notes and making observations, and will report back in a few months' time on the progress of my wriggly workforce.

Other wormeries for your apartment (prices exclude postage)

The OvO
The OvO is an ideal way to get started on a small scale or to educate children about the benefits of vermicomposting. This small plastic globe is a self-watering plant pot as well as a wormery, and comes complete with two soil biscuits and a packet of composting worms. Add water to the soil biscuits, worms to the soil, and vegetable scraps to the worms then watch them go. Cordon off the centre of the OvO with a toilet-roll tube to create a fertile place to germinate seeds.
Price: £16.98; www.beecycle.co.uk

Original Organics Original Wormery
This family-sized kit consists of a 100-litre bucket that comes with compost bedding, 150 junior and baby tiger worms and a calcified seaweed-lime mix to control pH levels. It's simply a case of opening the lid and dropping in your waste; there is a compression seal in case you're worried about odour and a tap to harvest the liquid feed. A 35-litre Midi Wormery is available for skinny couples or singletons.
Price: £51; www.originalorganics.co.uk

The Worm Works
Stack-system wormery that comes with three, four or five trays, collection tray and tap for liquid. Includes coir bedding, two packets of tiger worms and 2kg of lime mix. Can be used inside or outside.
Price: £89; www.thewormworks.net

Wiggly Wigglers Worm Café
An update of the classic Wiggly Wigglers Can-O-Worms, the Worm Café's hinged lid makes feeding your worms even easier. Ideally for outside use, the four-tray system is raised off the ground, and the recommended start-up kit includes a bedding block, 500g (approximately 1,000) of mixed tiger and dendrobaenas, 2kg of lime mix, 2kg of worm treat and a moisture mat.
Price: £99; www.wigglywigglers.co.uk

Eifion Rees is a freelance journalist

See also:

More from this author