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How to make an indoor worm bin (vermicomposting)

“About 30% of the waste that goes into landfills could have been rescued, could have been composted. We could really be reducing a lot of that by composting at home.”– master composter SungBin Park from the Lower East Side Ecology Center.

No matter how small your apartment, composting is an option. Thanks to the incredible digestive systems of red worms, to compost 3 pounds of your organic waste per week, all you need is:

  • An opaque tupperware container: at least 16” wide x 19” long x 12” deep.
  • A pound of composting worms: a worldwide list of where to purchase worms online.
  • Some bedding: wet newspaper scraps.
  • And of course, the food: your kitchen or garden waste.

We have a video where SungBin gives us an intro course on how to create and use a worm bin to turn your food waste into top quality soil for your houseplants: How to worm compost in a city apartment.

Here are step-by-step instructions from the Lower East Side Ecology Center for making your own indoor worm bin (they also sell worms and bins):


  • A plastic storage bin with approximately the following dimensions: 16″ wide x 19″ long x 12″ deep.
  • Plastic screen material.
  • Rubber cement.


  • Drill with 1/16″ bit and 2” keyhole attachment
  • Or nail and utility knife

Steps for construction:

  1. Use 1/16” bit to drill approximately 12 small holes in the bottom of your plastic storage container, or heat up a nail to punch small holes in the bottom.
  2. With the 2” keyhole attachment drill 2 holes on two opposite sides of your bin or use a utility knife to cut holes.
  3. Cut the plastic screen material to cover the holes on the side and use the rubber cement to glue to the inside of the plastic bin.

Once you’ve made the bin, now it’s time to make it into a home for your worms.

Pick a Place

Locate your bin where it will not freeze or overheat, temperature range should be between 40°F to 85°F:

  • Good locations: pantry, kitchen corner, garage or basement.
  • Do not place the worm-bin next to a radiator.
  • The worm-bin can be kept in a shady place outdoors from May through October, but needs to be inside for the winter (applies to NY… this depends on the winter temperatures where you live).

Bedding Down the Worms

Worms like to live under lots of moist paper or leaves, which helps them stay cool and moist, giving them fiber to eat.

  1. Use regular newsprint black or color ink paper, but no glossy inserts, and shred to make 1 inch-wide strips.
  2. To moisten the paper, soak it in a bucket filled with water.
  3. Squeeze out paper so it is not dripping wet, and fluff to fill the bin 3/4 of the way – that is 9” of fluffy, moist newspaper.
  4. Now, you can add your red wiggler worms. Put them on top of the bedding and watch them disappear, as they will naturally disperse into their new home.

Maintaining Your Worm Bin

Feed worms by always burying the kitchen-scraps underneath the newspaper. Add moist newspaper as needed to keep a 4” to 6” layer of bedding over the food.

DO Feed Your Worms:

  • All fruit and vegetable trimmings including citrus
  • Coffee grounds and filters
  • Teabags
  • Crushed egg shells
  • Used paper towels
  • Soft green plant trimmings

DON’T Feed Your Worms:

  • Meat, bones and fish
  • Dairy products and grease
  • Dog, cat or bird feces
  • Kitty litter
  • Woody prunings
  • Non-biodegradeable items such as plastic

All organic matter is broken down initially by naturally occurring microorganisms. To speed up this process kitchen scraps should be cut into small one-inch pieces. This initial ‘rotting’ process allows the worms to digest the organic materials.

Keep Bedding Moist

But avoid wet conditions. If your bin has too much moisture, add dry bedding, such as paper-towels, to absorb excess moisture and/or keep lid ajar. If bedding dries out on edges, spray to remoisten it.

Remove Some Worms

If more and more worms are in your box, you might want to remove some worms. Red wigglers make great gifts and can be put in outdoor compost piles. If no worms are removed, the population will self-regulate.

Harvesting and Using Worm Castings

Congratulations! You have produced your own natural fertilizer to top-dress your houseplants or to line planting holes in you garden. Street tree pits will also benefit from the vermin-compost. Worm-castings are full of beneficial microbes and nutrients to power new plant growth instead of wasting away in a landfill.

  • Harvest worm castings every two to three months to keep the worm population healthy, since castings become toxic to the worms over time.
  • Start the harvesting process by not feeding your worms for two weeks.
  • Then pile all the crumbly, dark worm-castings in one half of your bin, and place fresh bedding together with undigested paper, etc. in the other half.
  • Resume feeding your worms, but add all food to the fresh bedding.
  • Within two weeks worms will migrate to the new food and finished castings can be removed almost worm-free!!

Worm Bin Troubleshooting

Problems                                         Causes                                     Solutions
Worms are dying                             Too dry                                   Add water until bedding is damp
Extreme temperatures                                                                     Move bin so temperature is between 40°-80°F
All food and bedding eaten                                                             Harvest castings, add fresh bedding and food
Bin smells bad                                 Overfeeding                            Stop adding food and fluff up bedding
Molds                                              May happen spontaneously     Brush mold off affected surface
Moldy food was added                                                                    Remove moldy food and bedding

Fruit Flies!! (blech)

The annoying nemesis of otherwise happy worm owners is fruit flies. These little beasts seem to come from nowhere. Actually, their egg larvae may be present on skins of tropical fruit.

Make sure to do one of the following before the problems get out of hand:

  • Microwave or freeze tropical fruit skins and destroy larvae.
  • Add 3-4 tablespoons of lime to bin and raise the pH.
  • Create a fruit fly trap by pouring some wine or beer in a cut and inverted plastic bottle (remove and dispose of dead flies). Attach sticky flypaper on the underside of bin lid.