Composting Foodwaste | Solid Waste Division | Public Works & Utilities

Public Works & Utilities >> Solid Waste >> Composting >> Composting Foodwaste

Follow these step-by-step instructions to establish your worm bin, and with a little maintenance, your compost should be ready in a month or two!

Materials Needed:

* Worm bin (step 1)
* Bedding (step 2)
* Worms (step 3)
* Worm food (step 4)
* Gardening gloves (optional)

Worm Bin

Step 1: Worm Bin:

Get a worm bin:

build
buy one
or use your imagination and reuse a discarded (but clean) container, such as an old dresser drawer, trunk or barrel.

Use a sturdy container with a tight-fitting lid to keep pests out and moisture in. A shallow box about a foot deep is best as worms live near the surface to breathe.

You need about one square foot of surface area for each pound of foodwaste per week.

For outdoor bins:

Drill holes in the bottom for drainage.

For indoor bins:

Plastic Bins: Wood Bins

Drill holes on the sides and
bottom to be sure liquid doesn't accumulate. For indoor smaller wood bins: you do not need to drill holes.

The wood will 'breathe' naturally and absorb excess water.

Worm bin location, ideal temperature:

Worm bins can be used indoors year 'round and outdoors during mild weather. The advantage of portable bins is they can be moved when weather conditions change.

Ideal Temperature:

Worm bins should be located in a shaded or partially shaded area out of the hot sun and heavy rain.
If temperatures drop below 40 degrees F, bins should either be moved indoors or well insulated.
Recommended temperature is between 40-80 degrees F, but with added bedding, which acts as insulation, worms can survive short periods of freezing temperatures.

Step 2: Bedding

Bedding

Step 2: Bedding

Add bedding. Any of the following materials may be used:

Shredded newspaper (no colored pages or slick paper)
Corrugated cardboard
Coarse sawdust (from untreated and solid wood. No sawdust from treated wood, plywood or oriented strand board)
Dry leaves
Seaweed
Coconut coir fiber
Shredded copy paper and other non-glossy paper waste

Tips:

Try to vary bedding as much as possible to provide more nutrients for the worms and create a richer compost.
Add two handfuls of sand or soil to provide necessary grit for the worm's digestion of food.
Moisten materials(s) first by soaking in water then squeeze out water and fill the container with 4-6 inches of bedding materials.
After the bin is established, add more bedding when needed, such as if fruit flies appear.

Step 3: Worms

Worms

Step 3: Add worms

Red wriggler worms thrive on organic materials, such as foodwaste. Don't use nightcrawlers, as they live in soil and aren't ideal for food waste composting because they grow, reproduce and eat very slowly..

Locations to buy red wriggler worms

Step 4: Worm Food

Worm Food

Step 4: Feed the worms

Yes No

* Coffee & tea grounds
* Moldy bread
* Oats
* Egg shells & eggs
* Cereal (not too sugary)
* Corn bread
* Corn and bran cereal
* Fruits (cooked or raw)
* Vegetables
* Corn cobs (break in small pieces) * Meat
* Fish
* Bones
* Pasta
* Salt or salty food
* Dairy products
* Cooking oil

Tips:

Begin feeding your worms only a little at a time.
As they multiply, you can add larger quantities of food scraps.
After a few months, you can feed about a quart of food scraps (approx. one pound) per square foot of surface area each week.
To avoid fruit flies and odors, bury food under top layer of the bedding.
Worms prefer smaller-sized scraps and will eat quicker rather than large or whole pieces of food.
If the worm bin begins to smell bad, it could be a sign that you're adding more food than the worms can eat.

Next Steps: Worm Bin Maintenance & Harvesting Compost

Worm Bin Location & Maintenance

Graphic of worm under umbrella basking in sun.

Worm Bin Maintenance:

If you have the correct ratio of surface area to worms to food scraps, there is little to do other than add food. In about 2 1/2 months, there should be little or no original bedding visible in the bin, and the contents should be brown, earthy-looking worm castings.

Harvesting Compost:

It's important to separate the worms from the finished compost, otherwise, the worms will begin to die. As the proportion of castings increases, the quality of the environment for the worms declines. For the health of the worms, it's necessary to remove some of the compost and replace it with new bedding.

The simplest way to make room in a worm bin for new bedding and more garbage is to divide and dump.

Next Steps

Worm Bin Troubleshooting:

Assistance

Pierce County residents may contact our office for questions about composting. You may also consider signing up for one of our worm composting classes to learn how to compost.

Pierce County Public Works & Utilities
Solid Waste Division
9850 64th Street West
University Place, WA 98467-1078
Phone: (253) 798-2179
Fax: (253) 798-4674
E-mail: pcsolidwaste@co.pierce.wa.us