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Reprise: Vermicomposting or One Option for Composting in the City

First of a two-part series that first appeared over at, a sweet little online business with an eco-bent that I used to write for. They're taking a bit of a break at the moment, but are worth watching for and checking out when the time comes.  - JB

Photo courtesy of James Kemp at
Compost is a gardener’s best friend. The dark loam made from decomposed kitchen waste fuels healthy soils, brings helpful microbes, bacteria, and insects to the garden along with plenty of nutrients that plants need. Yet, organic urban gardeners, especially those able to grow only in containers, can find compost a challenge. Often, there is no backyard where a compost bin can be tucked, just a balcony or tiny patio. What to do?

Enter the worm.

Most people only think of worms as the little wiggle on the end of a hook meant to invite fish for dinner. Yet, worms do a great deal of the heavy-lifting that keeps soil healthy and fertile. Gardeners who find these slimy squigglers know worms are a sign that their soil is in good shape. It also turns out that worms are the urban grower’s composting ace in the hole, er, bin.

Vermicomposting uses worms, usually red wigglers, to make compost. Kept in a small box called a vermicomposter, the worms munch away on kitchen scraps (no meat or dairy, thanks). As they eat so they poop, and the resulting worm humus or worm castings are rich in nutrients that plants adore. According to the University of Nebraska-Lincoln Extension, “compared to ordinary soil, the worm castings contain five times more nitrogen, seven times more phosphorus and eleven times more potassium. They are rich in humic acids and improve the structure of the soil.”

For urban residents, vermicomposting is a real boon according to James Kemp, owner of, and importer of Australia’s Can-O-Worms vermicomposting system and a devoted vermicomposter since 2007. 

“The great thing about vermiculture for urban composters is the cleanliness, ease of "operation" and the fact that it can be done in tiny spaces. The Can-o-worms unit, for example, is only about 60cm in diameter, so it will fit onto most apartment balconies. So long as you follow a few easy steps, the worms are quite happy to be left alone if you have a trip out of town or are away for a while, they don't need a lot of attention. If the worms are happy and the environment inside the Can-o-Worms is running as it should be, then there is also no smell or unpleasant odor.”

Peo and Satoko Ekberg, sustainability consultants, use vermicomposting as part of their One Planet apartment scheme. The worms that live on their balcony helped reduce their home garbage dramatically.

Vermicomposting is also efficient. Kitchen scraps turn into hummus in roughly three to four months. In the meantime, Kemp suggests enjoying a cup of “worm tea.”

“Worm composting is a great balance- your kitchen scraps turn into a rich compost within a couple of months, you get a daily supply of worm tea (liquid fertilizer) and it's easy to run, no fuss, no mess etc. The liquid run-off from the composter or the "worm tea" looks like a strong black tea and can be diluted with water and used on your plants. It's best to use it fresh. We have a bucket under the tap on our Can-o-worms and let it fill up naturally. Every day or two we'll empty it and use it to water the plants,” said Kemp in an email interview.

Inspired and intrigued? Good! Next week we’ll give you all the tips and ideas you need to build, buy, and manage your own bin. 


Mel said…
Great info. We love vermicomposting around here and it's really amped up our composting efforts. Mel at

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