Coulter's Good Earth Farm
"Eat Local, Eat Better"
Good Gardening: How To
Vermicomposting 101

Congratulations on the entering the world of vermicomposting!  Using worms to recycle kitchen wast is a great way to reduce our garbage while creating a valuable organic fertilizer that we can use to grow more plants!  Vermi--meaning "worm" in Latin, and vermicomposting is not true composting, but rather the worms eat your garbage and their waste is left behind as a well-balanced, all natural fertilizer.

About Your Worms

These are not your ordinary earthworms, but rather one of a few types of worms generically called "redworms" being Eisenisa foetida or Lumbricus rubellus.  Unlike other earthworms that live underground, these species are native to the upper layers of soil in forests, where they feed on leaf litter.  Therefore, they are perfectly happy eating your kitchen waste while confined in a worm bin.  They reproduce quickly, so you can start with a few and end up with a lot.  As long as you take proper care of your worms, they'll just keep on reproducing themselves, allowing you to increase the size or number of your worm bins.

How to Care for Your Worms

New worm bins are started with a bit of peat moss and some shredded newspaper.  A little sand provides the grit needed in their gut to help the worms digest their food.  At this point, all you need to do is add your kitchen scraps.  Coffee and tea grounds, and all vegetable and fruit scraps are perfect food for your worms.  You might want to avoid onions and garlic, which are a little too strong, and may repel the worms.  NO MEAT or OILS, as these guys are strictly vegetarian.  If you find yourself without enough kitchen scraps, oatmeal makes a good feed supplement.  Egg shells are a great addition to the bin, and while the worms don't eat them, you'll often find them inside the empty shells.  When the vermicompost is finished, the egg shells add a good source of nutrients for your plants.

You don't have to feed your worms every day.  In fact, people over feed their worms.  If you see that the worms aren't able to keep up with the scraps, then back off for a few days.  If you see that most of the scraps are gone, then add a few more.  If you find that you have more scraps than the worms can eat, you can start another bin or move them to a bigger one.  Their population will increase to fill up the bigger bin and handle more scraps.

Will My Bin Stink?
If properly tended, the vermicompost bin shouldn't stink.  If you add a lot of high-moisture, high-sugar scraps, like fruit, you might attract fruit flies.  Keeping a thick layer of shredded newspaper as the top layer helps prevent excess moisture. The worms will incorporate the newspaper into the compost, so you'll have to keep renewing this layer.  Burying new scraps in the bin helps prevents any odors and fruit flies.

The design of our bins allow excess moisture to drain out and collect in the bottom pan.  When you see liquid accumulating, just empty it out.  This is a an organic fertilzer and is great for use straight on your plants!

Harvesting the Vermicompost

When the bin starts to get full, it's time to harvest your vermicompost.  Stop adding scraps for a week or so to allow the worms to completely finish their work. Then, you must separate the worms from the finished vermicompost.  Here are two methods:

Dry and Scrape:  In this method, you take the top off of the bin and let the top layers dry out.  How long this takes depends on the weather, but if you are doing it outside, make sure your worm bin doesn't overheat.  As the top layers dry out, the worms will move down into the bottom of the bin.  You can then scrape off the top layer of vermicompost.  Finished vermicompost should be dark colored and have few recognizable traces of scraps.  Use it right away or let it dry further, bag it up, and use it when you need it.  Leave enough worms in the bottom and just restart the bin, adding fresh peat moss, a bit of sand, newspaper, and kitchen scraps.

Dump and Pick:  In this method you just dump out the bin on a flat surface and pick out enough worms to get another bin started.  After you get enough worms to restart your bin, let the vermicompost and the worms remaining in it, dry out completely.  It is then ready for use, and the dead worms will just add to the richness of the vermicompost. Then, restart your empty bin as previously stated, adding the worms you've saved out.

In either method, you won't be able to save all the worms, so don't drive yourself crazy trying to pick them all out.  They naturally die and are replaced in the bin on a regular basis, so you only need to save enough to keep this natural cycle going.

Do place your bin in a cool place out of the sun.  Basements and under the kitchen sink are perfect.  These worms do best in temperatures around 50 to 70 degrees.  If a clear bin is left in the sun, or in a very hot place, it will heat up and kill the worms.  A garage is a good place as well, but if it is unheated, the worms must be protected from freezing in the winter.  These worms can't take extreme cold and won't survive the winter outside.

Do add some of your worms to your outside compost pile in the summer.  They'll eat happily there, speeding up the decomposition, until they die out in cold weather.  Save some of your worms inside, and you can add more the next spring.

Good luck and welcome to the world of vermicomposting!

Chris Coulter

This article is the original intellectual property of Christopher B. Coulter and should not be reprinted without express permission from the author.

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