It all begins with the soil. Worms are the great transformers of landscape through eating and digesting. They can consume a patch of stones and over time turn it into a fertile field. Worms continually pass soil through their intestinal canals, keep anything they can use for food, and then "cast" the rest. With indoor worm composters, these creatures can take your coffee grinds, lettuce scraps and apple cores and turn them into fertilizer castings that your plants will love.
What You Need
Materials
Small stainless steel bucket with carbon filter
Kitchen scraps, like salad greens, egg shells, and coffee grounds
A minimum of 1,000 red worms
A container, size varies (see instructions)
Newspaper, sawdust, cardboard, or straw, dampened
Contact paper (optional)
Tools
Electric drill
Instructions
Different worm composters will come with instructions and bedding, but here are a few basics for getting started.
1. To start with, keep a small stainless steel bucket with a carbon filter in its lid next to your sink for scraps. The carbon filter is so that no odors escape. Particularly early on, try to pick out vegetables for your worms that are non-acidic, like salad greens rather than onions. Also eggs shells that have been ground up, tea bags, and coffee grounds can go into the mix. Later, when the worms become heartier eaters, you can increase the volume and variety of vegetables and fruit that you feed them, but avoid oily food, clippings from house plants or any animal matter. I also try to only give mine organic produce so that there are no traces of pesticides in their food.
2. Order your worms. You need a minimum of 1,000 red worms to start with, and if you have a large commercially built composter, start with 2,000. It sounds like a lot, but it's not. They actually reproduce, but will not overpopulate.
On Containers: A reusable plastic storage container works if you have this, but you can also use wood or other non-permeable materials. Just make sure there are air holes so the worms can breathe, and a lid, so they don’t escape. Adjust your container to the size of your apartment. If your kitchen is tiny and this might be tucked under the sink, use a box about 6-8 inches deep, 24 inches long, 6-8 inches wide. For this size order about 10,000 1,000 red worms. If you have a pantry or closet off your kitchen, or even a corner for them, you could use a larger box, or order a larger, layered worm composter, such as the Can O'Worms. For this size order 20,000 2,000 worms. The worms are shipped, but they do just fine.
Here are a few places from which you can order worms:
3. Drill or poke air holes into your plastic container.
4. Add bedding to the container. Pre-purchased composters, such as those you can get from CompostBins or Eco-Outfitter, come with bedding, but if you want to make your own, use newspaper, old cardboard, sawdust, and even pieces of straw. (Some instructions will tell you to use manure, but I avoid this in case the animals were given any de-worming medication.) Dampen this slightly, so that it feels like a wrung sponge.
5. Empty the worms into the tray. They don’t like sunlight, so will quickly dive down into the matter if you leave the lid opened and exposed to light for a few moments. Then cover them with dampened newspaper.
6. Place a few handfuls of your kitchen waste here—if you chop it into smaller pieces it will be easier for the worms to eat. You’ll need to adjust the amount as you get to know them. Start with smaller amounts of scraps, ½-1 cup at a time. If the table scraps rot, remove them from the composter. If the worms are eating them, add more, but as a rule of thumb, you should never have more than a 1/2 inch layer of food scraps across the surface area. Then cover the food with damp newspaper. (It shouldn't be soaking wet, just damp.) Store your container in a dry, temperate place. 70 degrees is ideal.
Note: Signs that you are overfeeding your worms include black flies in your compost bin. If you find black flies, remove some of the food and in the future give them less. I like to feed my worms smaller amounts at more frequent intervals. Mine are a little fussy and don’t like rotted produce.
7. It should take 3-6 months before you can begin harvesting your castings. You can do this a number of ways, but the least messy is to harvest your castings in a homemade, single level container. Push your worms and vermicompost to one side of the container and lay fresh bedding and food on the other side. The worms will migrate over and then you'll be able to harvest the composted matter from the other side. After you remove it, add new, fresh bedding. Or, sometimes if I’m feeling lazy, I’ll just root around in the worm bin with a small trowel and pull out castings, and pop them into my houseplants. Sometimes you scoop up a worm or two, but they are good for the plants as well. You can mix the castings in to potting soil and then keep adding it by layering it over the soil in your planters. As you water, the nutrients will drain into the soil.
To fertilize, sprinkle over the soil of your houseplants. If you have a bigger harvest, these can be saved in bags and then mixed with potting soil when starting new plantings. One big advantage to using worm castings is that you really can’t over-fertilize with it they way you can with store-bought fertilizers.
Additional Information:
For more information on composting, check out these resources:
About the Author:

Maria Finn has written for Saveur, Metropolis, Forbes, The New York Times, ABC.com, and The Los Angeles Times. She is the founder of Prospect & Refuge, a garden-design and installation firm and also writes the weekly newsletter/blog City Dirt, dedicated to adventures in urban gardening. Her newest book, A Little Piece of Earth: How To Grow Your Own Food in Small Spaces, will be released on February 16. She lives on a houseboat in Sausalito, California.
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(Images: Maria Finn. Originally published 2010-02-05)











Shaw's Original Fir...
This is so cool & perfect for small dwellings! I can't wait to try it.
Oh man, if my husband thought a guinea pig for a pet was a possibility for us because it eats vegetable scraps, then he's going to love the idea of worms! I'm excited to tell him about this.
I'm wondering: does it smell, and does it attract fruit flies ? (I've already more than I need)
I have been worm composting for close to 2 years and I encourage everyone to try it. I have given worms to 2 friends to get them started also. I am fairly sure that 10,000 worms is a little extreme, your worms will self-regulate their population, but I'm pretty sure I only started off with around 100 or so. The first summer when I started my bin, I did have a problem with fruit flies, but it turned out it was because I was overfeeding. Once I slowed down on feeding, I had no problem with flies. And there is definitely no smell (or there shouldn't be if your bin is healthy) I can literally stick my face right in my worm bin and the only slight smell is of fresh earth. And yes, my husband does think it's weird, but I think he got over the ick factor pretty quickly, he even occasionally feeds them.
I found this site to be very helpful when I first started: http://www.redwormcomposting.com/
good luck everyone!
Does this require any temperature regulation? I'd like to try this, I think my son would be really interested in watching. We have a tiny kitchen with no storage area, could I keep them in a cool garage, and then move to our porch with warm weather?
We started composting on our apartment balcony in a 30-gallon storage tub with great success. When we moved halfway across the country last summer we brought a small cooler full of worms with us and started over. With just a small number of worms, they have taken off and are doing great.
To keep down fruit flies, always cover kitchen scraps with shredded paper, cardboard, or egg cartons. We also nestle a small cup of vinegar in the corner to help reduce their numbers.
I started doing this as a christmas present to myself. I bought the "can-o-worms" composter which was pricey and if I had less floor space I wouldn't have picked, but its so awesome and easy to use. It has a tap in the bottom to drain off, the vent holes are small and so even if I had fruit flies (which haven't seen) they couldn't get out, and it is tiered so you jsut make the worms climb up to the top tier before you harvest and start over. I'm loving it, my plants already like the tea and I can't wait till I hit the last level and I get to harvest.
Instead of keeping a bucket on the counter I developed a different method. I have a huge wide ceramic bowl and I keep it in the freezer. when I chop veggie scraps I throw them into the bowl, and then when I'm ready to feed the wormies I clear a little hole in the bin and put a pile of frozen scraps in. I learned this from my friend's mom- it kills fruit fly eggs, and if you don't move scraps into the composter everyday its a really easy fix. i also just like not having a lidded container that I have to open when i'm cooking- less chance of getting bacteria transferred to the fresh food/my hands.
Also I have a paper shredder and make a deep deep bedding for my worms out of my non glossy/non plastic mail in the shredder. Its great. I pay my bills, file and then put the other pile straight through the shredder. Paper waste makes me so frustrated- there's so MUCH of it, and this way it does some good. I find in the type of bin I have it holds the moisture in just fine, and a deep enough layer means there's rarely a smell.
I will say there are some odors that come with the bin sytem I have going. Its not a lot, and its not all the time, but I've noticed sometimes something I add will add a faint composty undernote to the apartment- especially if I haven't drained off the bin recently. Its not a rot sort smell, just a little whiffy kind of odor- kind of a wet dog smell. So if the occasional mild scent will send you round the edge, you might want to do it in a well ventilated area or your patio.
i wouldnt mind keeping worms, but having to move them in order to get the castings... it's a bit too icky :p i also would rather keep them out on the balcony but they wouldnt do too well in the cold i presume!
We have used a 5-gallon Home Depot bucket with several small (1/16") holes drilled in the bottom for drainage. I started by tossing some leftover soil in there, added some night crawlers from Academy, and just put my vegetable scraps, tea bags/coffee grounds, and eggshells in there every couple of days. Last night I just turned it over into another identical bucket and scooped the composted dirt off the bottom and repotted my plants with it. Also got a good look at my worms - all nice and fat now! Oh and I spotted several little baby wormlets.
The smell was kinda bad but it's only bad when you start digging around in it and exposing all the decomposing stuff. I'm excited to see how my little plants like it.
I used the Worm Factory for my vermicomposting adventure. Boy it was hard at first! It was a trial and error process as I didn't know much about Red Wigglers at first. I spent up to 3 hours almost every day Googling and finding answers to my vermicomposting questions and this article was one of the articles online which really helped me a lot. Thanks!
I know that handling worms is an issue for a lot of people. But you can purchase a premade worm composters that makes the process much more simple. The worms eat the food on the bottom tray, then move to the next tray up when the food runs out. Compost minus the worms is left in the bottom tray, so you can simply add it to your garden. Also, if you don't want to deal with worms, then you can do Outdoor Composting but it is slightly more involved.
You've got the worm count wrong. You listed 10,000 or 20,000 worms depending on the size of the bin. This is way too many worms! You probably meant 1,000 to 2,000.
I started with 1,000 in a bin that is 22.5 L x 17.5" W x 12.5" high and that was plenty for this bin. Click here for more info on worm composting.
I'm not so sure I can do worms inside... it's just me
I have a homemade worm bin under my kitchen sink. Very convenient and makes me feel good. It's made out of a giant tupperware tub. I set it on top of a wire shelf that I can use to slide it in and out, and put a second lid under the shelf to catch drips. The only problems I've had occasionally are mold, which only happens with sweet things like pear peelings, and an overly wet environment, which will cause the worms to crawl up the bin to try to escape! If there's anything really moldy in there I pull it out, but both problems can easily be remedied by adding more cardboard and paper bag pieces and mixing it up. Pieces of egg cartons are handy for aeration. I keep latex gloves under the sink for when I want to really dig in there.
My husband's capstone project in school recently was vermicomposting - a proof of concept for doing so on a scale such that the wastes from a restaurant could be dealt with via worms. So he had extras and brought them home. We keep them in the workshop - no room in the house - and he rigged up a way to keep them relatively warm so they wouldn't expire this winter. They don't have to bask in warmth, but they of course they shouldn't risk freezing. The cooler they get the slower they process scraps. We use an old blender/processor to get scraps finer - no big chunks go into the bin. We're loving the tea that drains off ... full of good stuff for our gardens. Yay worms!
I second Sandie Anne's comment about the count being off. Earlier in the post, it says 1,000 are good to start and that larger commercial bins would take 2,000. But a little farther down in the Containers section, it says 10,000 and 20,000. This is a great post otherwise and re-posting it might be the kick I need to finally order my worms (have had a bin ready to go-minus damp bedding-for MONTHS).
But could you edit the numbers so people who are checking this out since the re-post order a reasonable amount?
Are there any guidelines for the temperature of the area where you store the bin?
I've heard of this concept before but never tried it - mostly because I'm not great at gardening.
One question: Is it possible to create a terrarium that includes living plants as well as the composting and worms? Possibly divided in two in a large container, with a side devoted to composting and a side for gardening, but letting the worms kind of travel freely between both sections?
1000-2000 worms is completely sufficient to start a bin, and the bin should be kept in a place with a temperature between about 55 and 77 degrees Fahrenheit. Check out www.theurbanworm.com for some useful tips and resources. The Worm Factory bins also come with a quick tips lid and a manual to help beginners get started. Keep us posted on how the projects go!
www.theurbanworm.com
been there, done that.
I was already pressed for time keeping my place clean and finding time to do laundry. This just added another chore. Was not a good idea for me.
Here is a cute indoor vermicomposter called the City Bin. Looks like they have an IndieGoGO campaign going on right now:
http://www.indiegogo.com/CityEarthworm